StemCell Therapy

This article will introduce you to a number of herbs that can safely be relied upon to strengthen the immune system, protect you from a wide array of disease-causing organisms and assist you in maintaining vibrant and robust health.

Your immune system is an incredibly complex interaction between organs, glands, body systems, surfaces, cells and chemicals. This symphonic concert of processes requires nourishment in order to function optimally.

Many herbs and other substances are used by cultures around the world to nourish and support immunity and protect us from a multitude of disease causing micro-organisms, including influenza, the Herpes simplex virus, or fungal growths such as Candida. I know a few of these protective and immune strengthening herbs on an intimate level, and would like to introduce you to some of them here. We'll cover astragalus, usnea, sage, garlic, honey, shitake and reishi mushrooms, hyssop, and St. Johns wort.

Milk Vetch Astragalus membranaceus Astragalus has been growing in our gardens for over ten years now. It is quite hardy, and withstands even the coldest Maine winter. It grows into a large bush, quite feathery, bright green and very pretty looking, with dainty, fan-like yellow flowers in mid to late summer.

Oftentimes in nature you will find that the gifts of a plant make themselves known to you in the manner in which the plant grows, the conditions it requires, and its degree of hardiness. When a plant thrives no matter what, take a deeper look, and you may find that it will help you to do the same. Astragalus strikes me as such a plant. Rugged, resilient, strong, powerful, long-lived, graceful, and elegant.

Astragalus is a tonic and restorative food and a potent medicine plant. The Chinese have been using this plant to strengthen immunity for centuries. They say it "strengthens the exterior", or protects against illness. Known as Huang-qi, astragalus is written about in the 2,000 year old Shen Nong Ben Cao Jing, and is still considered to be one of the superior tonic roots in traditional Chinese medicine. It's name literally means yellow leader; yellow referring to the inside of the root, and leader to its medicinal potency.

Mildly sweet, and slightly warm, astragalus invigorates vital energy, is restorative, strengthens resistance, restores damaged immunity, promotes tissue regeneration, is cancer inhibiting, antiviral, adaptogenic, protects and strengthens the heart and the liver, is tonic to the lungs and enhances digestion.

Many scientific studies have verified its immune enhancing action. Astragalus is a powerful "non-specific" immune system stimulant. Instead of activating our defense system against a specific disease organism, astragalus nourishes immunity by increasing the numbers and activity of roving white blood cells, the macrophages.

As an immunostimulant, astragalus engages and activates every phase of of our immune system into heightened activity. In one study, the activity of macrophages was significantly enhanced within six hours of treatment with astragalus, and remained so for the next seventy-two hours.

In Chinese medicine astragalus roots are said to tonify the Spleen, Blood, and Chi. They are used as a tonic for the lungs, for those with pulmonary disease, frequent colds, shortness of breath, and palpitations. Astragalus is also prescribed for those who suffer from fatigue, from any source, chronic nephritis, night sweats, uterine prolapse, or prolapse of the rectum.

It's tissue regenerating and anti-inflammatory abilities make astragalus an excellent ally to heal chronic ulcerations and persistent external infections, as well as to heal hard-to-heal sores and wounds, and to drain boils and draw out pus. Astragalus processed in honey is a specific against fatigue, used to boost vital energy, to nourish the blood, and also against incontinence, bloody urine or diarrhea.

In a study conducted by the University of Texas Medical Center, in Houston, researchers compared damaged immune cells from cancer patients to healthy cells. Astragalus extracts were found to completely restore the function of the cancer patients' damaged immune cells, in some cases surpassing the health and activity of the cells from healthy individuals.

The extract of astragalus was also shown to significantly inhibit the growth of tumor cells in mice, especially when combined with lovage Ligustrum lucidum. According to a study reported in Phytotherapy Research, astragalus appears to restore immunocompetence and is potentially beneficial for cancer patients as well as those suffering with AIDS. It increases the number of stem cells present in the bone marrow and lymph tissue and stimulates their differentiation into immune competent cells, which are then released into the tissues, according to one study reported in the Journal of Traditional Chinese Medicine.

Astragalus also stimulates the production of Interferon, increases its effectiveness in treating disease, and was also found to increase the life span of human cells in culture.

Astragalus protects adrenal cortical function while undergoing chemotherapy or radiation, and helps modify the gastrointestinal toxicity in patients recieving these therapies. Chinese doctors use astragalus against chronic hepatitis, and many studies have demonstrated that astragalus protects the liver against liver-toxic drugs and anti-cancer compounds commonly used in chemotherapy, such as stilbenemide. When used as an adjunct to conventional cancer treatments, astragalus appears to increase survival rates, to increase endurance, and to be strongly liver protective.

Astragalus helps lower blood pressure, due to its ability to dilate blood vessels, and protects the heart. Scientists in the Soviet Union have shown that astragalus protects the heart muscle from damage caused by oxygen deprivation and heart attack.

According to reports in the Chinese Medical Journal, doctors at the Shanghai Institute of Cardiovascular Diseases found that astragalus showed significant activity against Coxsackie B virus, which can cause an infection of the heart called Coxsackie B viral myocarditis, and for which there is no effective treatment. In a follow-up study, researchers found that astragalus helped maintain regular heart rhythms, and beating frequency, and that Coxsackie B patients showed far less damage from the viral infection (as much as 85%).

In Chinese medicine, astragalus is often combined with codonopsis. This compound is said to strengthen the heart and increase the vital energy, while invigorating the circulation of blood throughout the body. It is also traditionally combined with ginseng, and used as a tonic against fatigue, chronic tiredness, lack of energy, enthusiasm, or appetite, and to ease "spontaneous perspiration" or hot flashes.

Japanese physicians use astragalus in combination with other herbs in the treatment of cerebral vascular disease. According to a research paper published by Zhang in 1990, adolescent brain dysfunction improved more with a Traditional Chinese Medicine formula containing astragalus in combination with codonopsis and other herbs than with Ritilin.

Integrating astragalus roots into your winter-time diet, as the Asians have been doing for years, turns out to be a very good idea. Scientists have demonstrated that astragalus will not only prevent colds, but cut their duration in half. Astragalus possesses strong antiviral properties, and in one study regenerated the bronchial cells of virus-infected mice.

Astragalus has been safely used throughout Asia for thousands of years. The Chinese typically slice astragalus roots and add them, along with other vegetables, to chicken broth to create a nourishing and tonic soup. Discard the root after cooking, and consume the broth. No toxicity from the use of astragalus has ever been shown in the millennia of its use in China.

The genus Astragalus is the largest group of flowering plants, with over 2,000 different species, most of which are found in the northern temperate regions. Plants in this genus are amazingly diverse, some are nourishing and medicinal, some useful as raw materials, and others, such as the locoweeds, are toxic. Astragalus membranaceus grows in the wild along the edges of woodlands, in thickets, open woods and grasslands. It is native to the Northeastern regions of China, but grows excellently in Maine soils and temperatures, as do most Chinese medicinal plants we've attempted to grow thus far. Astragalus appreciates deep, well drained, somewhat alkaline soil.

Seeds are easily gathered and when planted in the fall require no prior soaking. They will germinate the following spring as soon as conditions are right. The seeds have a hard seed coat, and some people nick the covering with a file, or soak the seed overnight to hasten germination. Give each plant plenty of room, as much as a foot all around, and harvest after the fourth or fifth year of growth. Use whole or sliced, fresh or dried root for tinctures, honey, infusions, syrup, or in soups.

Astragalus Tincture

St. John's wort Hypericum perforatum St. John's wort contains numerous compounds that possess documented biological actions, and are the focus of much study. Those constituents that have generated the most interest thus far, include the naphthodianthrones, hypericin and pseudohypericin, a wide range of flavonoids, including quercetin, quercitrin, amentoflavone and hyperin, and the phloroglucinols, hyperforin and adhyperforin. Also of interest to researchers are the essential oils, and xanthones.

Wise herbalists have always used the whole herb, and researchers agree, that it is an interaction between the many constituents in St. John's wort, rather than any one active ingredient, that is responsible for the wide range of beneficial actions this healing herb offers.

All parts of the herb are used medicinally, with hypericin content concentrated in the buds and flowers, and also present in top and bottom leaves, as well as the stem, though to a lesser degree.

Activity of Constituents:

Amentoflavone is antiinflammatory and antiulcer.

GABA is a sedative.

Hyperforin is an antibacterial agent active against gram-positive bacteria, is wound healing, a potential anticarcinogenic, and a neurotransmitter inhibitor.

Hypericin is strongly antiviral

Proanthocyanidins are antioxidant, antimicrobial, antiviral, and vasorelaxant.

Pseudohypericin is antiviral and

Quercitrin is a MAO inhibitor, as are the Xanthones.

Xanthones are antidepressant, antimicrobial, antiviral, diuretic, and cardiotonic.

St. John's wort is an excellent wound healer. It possesses strong antimicrobial properties, is a significant antifungal and antibacterial agent, and is especially effective against gram-positive bacteria. It inactivates Escherichia coli at dilutions of 1:400 or 1:200, and is also active against Staphloccus aureus.

Two constituents of the herb, hyperforin and adhyperforin possess antibiotic effects stronger than that of sulfonilamide.

Burns heal rapidly with the application of St. John's wort. In one study using St. Johns'wort oil, first, second, and third degree burns healed at least three times as rapidly than those treated with conventional treatments, and scaring was minimal. Orally administered St. John's wort tincture demonstrated a remarkable healing of incisions, excision and dead space wounds, and has also been shown to inhibit keloid formation.

Studies indicate St. John's wort may enhance coronary blood flow as well as hawthorn, due to the activity of the procyanidins. It significantly increases the production of nocturnal melatonin, which means taking it will help you sleep better, and feel better.

St. John's wort has also shown promise in the treatment of chronic tension headaches, and also appears to be liver-protective. It is a proven antidepressant, best used by those who are mildly to moderately depressed. It is also historically used to treat neurological conditions such as anxiety, insomnia, restlessness, irritability, neuralgia, neuroses, migraines, fibrosis, dyspepsia, and sciatica.

St. Johns wort is an ally when dealing with any fungal problem, such as candida (infusion as sitz bath), thrush (infusion as mouth wash), or an infection on the skin or nails(frequent soaks in infusion). Frequent applications of St. Johns wort oil will also help in healing these infections.

Use the oil to rub on to tired, sore, achy, painful, overworked muscles. St. Johns wort oil is legendary for relieving the pain and inflammation of back-ache, stiff neck, sore shoulders, bad knees, tennis elbow, and anything else that hurts.

St. Johns'wort has shown to be of considerable benefit to patients with Acquired Immune Deficiency Syndrome. (AIDS)

In one study, 16 out of 18 patients stabilized or improved during a 40 month period during which they were treated with St. John's wort. Only 2 of the 16 experienced an opportunistic infection during the time they took the herb.

Many studies have proven that St. John's wort inhibits a variety of viruses, including herpes simplex types 1 and 2, and HIV-1 viruses associated with AIDS. Researchers have concluded that both hypericin and pseudohypericin are uncommonly effective antiviral agents.

The antiviral activity of St. John's wort appears to be somewhat photo-dynamic, involving a photoactivation process to become more intensely effective. Internal use of St. John'swort is not recommended if you are currently taking a pharmaceutical antidepressant.

St. John's wort Tincture

St. John's wort Oil

Sage Salvia officinalis The ancients used aromatic sage to bring the virtues of wisdom, strength and clear thinking. Modern day researchers in Great Britain found that sage inhibits the breakdown of acetylcholine, and so helps to preserve the compound used to prevent and treat Alzheimers.

Sage is loaded with antioxidants, so is anti-aging, and also offers lots of calcium, magnesium, the essential oil, thujone, flavonoids and phytosterols. It is sedating and soothing, and has a tonic effect on the nerves.

Sage is a potent broad spectrum antibiotic, and immune stimulant. It possesses antibacterial, and antiseptic properties and is active against Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, Pseudomonas aeruginosa. E. coli, Candida albicans, Klebsiella pneumoniae, and Salmonella spp.

Some native tribes like the Mohican, commonly chewed the leaves of sage as a strengthening tonic, and people all over the world use sage to build strength and enhance vitality.

Expectorant and diaphoretic, sage is especially effective against sore throat and upper respiratory illness, and infections where there is an excess of mucous. Sage dries up secretions. Sage is also traditionally used, and effective against, dysentery. Its astringent tannins make it an ally for healing mouth sores, canker sores, bleeding gums, and gingivitis, when used as a mouth rinse. A study done in Germany showed that drinking sage infusion on an empty stomach, reduced the blood sugar levels in diabetic patients.

In Italy sage is very commonly used as a seasoning herb. One cannot help but notice the vibrant health and strength of the elder people, which I attribute, at least in part, to their copious use of sage in the diet.

Sage Tincture

Antibiotic Spray

Garlic Allium sativum

Garlic is not only antibacterial, but antiviral, antiseptic, antiparasitic, immune-stimulating, antispasmodic, hypotensive, diaphoretic, antiprotozoan, antifungal, anthelmintic, and cholagogue.

You can rely on the regular use of this spice to keep your body toned and functioning optimally. It will help keep that all-important and vital organ, the heart toned, help keep blood pressure down, as well as help lower cholesterol. Repeated studies have shown that garlic has a beneficial effect on the heart and circulatory system. Chop some into your salad, throw it, simmered in olive oil, over noodles and sprinkle with parsley.

Garlic is rich in antibiotic powers and strengthens the immune system. It is active against both gram positive and gram negative bacteria, including Shigella dysenteriae, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Escherichia coli, Streptococcus spp., Salmonella spp., Camphylobacter spp., Proteus mirablis, and Bacillius anthraxis.

Garlic is also active against herpes simplex, influenza B, HIV and many other serious illnesses. Note that it is active against the food-borne pathogens so often found in commercial foods, Shigella, E. coli, and Salmonella. Garlic kills bacteria in the gastrointestinal tract immediately on contact. To treat an active intestinal bacterial infection, consume lots of raw or cooked garlic, or take garlic capsules.

Garlic in the diet has also been shown to have a beneficial effect on those dealing with cancer, stress, and fatigue. Garlic stimulates the isles of langerhans, increases insulin production, and lowers blood sugar levels, thus aids diabetics in the control of this debilitating disease.

Garlic also helps increase the senovial fluids, and so is an ally for those dealing with arthritis. The sulfur in garlic helps break up the crystallization of uric acid in the joints, and so aids in the relief of gout. Garlic stimulates the brain and has a positive effect on brain functioning, helping to keep us alert and energized. Scientists have found that garlics anti-aging properties not only slowed the destruction of brain cells, but also caused new brain neurons to branch out. An old Ukrainian recipe to keep the mind sharp includes one pound of garlic, ground and added to a jar with the juice of 24 lemons. Leave covered for one moon cycle, then take one teaspoon each night.

Honey Honey is, an ancient Islamic saying goes, the food of foods, the drink of drinks, and the remedy of remedies. The ancient Greeks, Romans and Egyptians all kept honeybees, and extolled the virtues of honey. Some call honey a sweet medicine of heaven, others, elixir of long life. I use honey everyday and you probably should too. Heres why:

Honey is a rejuvenating, revitalizing, invigorating, natural antibiotic substance created by those magical insects, bees. Bees have been called messengers of the gods, and were associated with Great Goddess since the most ancient times. Many legends hint that bees, and their special creation, honey, played a very important role in our human development. It is said that the gifts of honey are long life, good health, and reverence for spirit. Honey has an ancient reputation as a life force increasing, immune strengthening, potency promoting, aphrodisiac elixir.

Honey consists of invert sugar (fructose, dextroglucose) and other sugars. It also contains a complex assortment of enzymes, antibiotic and antimicrobial compounds, organic acids, minerals such as iron, copper, phosphorus, sulfur, potassium, manganese, magnesium, sodium, silicon, calcium, iodine, chlorine, zinc, formic acid, and high concentrations of hydrogen peroxide. Honey also contains varying degrees (it depends on what flowers and herbs the bees are taking their nectar from) of vitamin C, the entire B complex, vitamins D, E, and K, pantothenic acid, niacin, and folic acid, amino acids, hormones, alcohols, and essential oils.

Honey can, and should be, thought of as a super food. It is a live food, stores its vitamins and minerals indefinitely, and is very easily digested by the body. Honey is an all around health and vitality enhancing substance. Wildflower honey, the concentrated nectar of wildflowers, the essence of all the combined medicinal qualities of all the diverse and abundant wild herbs, is thought to be the most medicinal.. All natural, unheated honey is antibiotic, antiviral, antifungal, anti-inflammatory, anticarcinogenic, expectorant, antiallergenic, laxative, antianemic, tonic, immune stimulating, and cell regenerating.

Bees gather the nectar from flowers and store it in their stomach while transporting it back to the hive. During their transport, the dew-laden nectars become concentrated by evaporation. The nectars also combine, in some as yet unexplained way, with the bees digestive enzymes, producing entirely unique compounds. Scientists have measured over 75 different compounds in honey, some of them so complex they have yet to be identified. One thing we can identify however, is the fact that when used as a consistent additive to food and drink, honey increases vitality, energy, immunity, libido, and life force.

Honey is proven more effective than any pharmaceutical antibiotic in the treatment of stomach ulceration, gangrene, surgical wound infections, and speedy healing of surgical incisions. Honey is unsurpassed for the protection of skin grafts, corneas, blood vessels, and bones during storage and transport. In fact, honey is such an excellent preservative of living tissue that it was commonly used to keep dead bodies from decomposing while being transported back to their homeland for burial. After his death in a foreign land, Napoleon was sent home in a huge vat of honey.

The fact that fist size ulcers and third degree burns heal beautifully with frequent applications of pure raw honey is clinically proven, and something I can personally attest to. A few years ago, I got a large third degree burn on my heel during a misstep on a motorcycle tailpipe. It was a deep wound and definitely hampered my ability to get around all that summer. I soaked my burned foot morning and night in lavender and rose salts and after each soaking applied a bandage liberally smeared with pure honey directly over the burn. I kept a thick layer of honey over that burn for a couple of months, and tried as much as possible not to walk on it. Today there is barely a trace of that huge burn hole on the heel of my foot. Since that time, honey is my first treatment of choice for any burn, first, second or third degree, any wounds, no matter how deep, skin ulcers, impetigo, and infections. I just keep whatever it is covered with a thick layer of pure honey. And keep eating it by the spoonful, or drinking it in water, or as mead, depending on what you are trying to nourish and heal.

Honey is active against staph Staphylococcus aureus, strep Streptococcus spp., and Helicobacter pylori, responsible for stomach ulcers, and enterococcus. Honey is also one of my top choices for treating any respiratory condition, whether a cold, flu, or respiratory infection. Honey will be your ally against bronchitis, chronic bronchial and asthmatic problems, rhinitis and sinusitis. Those dealing with chronic fatigue, any wasting disease, a depressed immune system, will all feel the benefits of integrating this sweet medicine of the bees into their daily diets.

Syrups made with pure honey

Usnea Usnea spp. Usnea, or old man's beard as it is commonly called, is a common lichen found hanging from trees around the world. It possesses strong antibacterial and antifungal agents and is a potent immune stimulant.

Usnea has been shown to be more effective than penicillin against some bacterial strains. It completely inhibits the growth of staphylococcus aureus, streptococcus spp., and pneumonococcus organisms. Usnea is effective against tuberculosis, triconomas, candida spp., enterococcus, and various fungal strains, and has also been reported active against Salmonella typhimurium and E.coli.

Usnea is actually two plants in one. The inner plant looks like a thin white stretchy thread or rubber band, especially when wet. The outer plant gives usnea its color and grows around the inner plant. The inner part is a potent immune stimulant, the outer part strongly antibacterial.

Among the known constituents of usnea are usnic acid, protolichesterinic acid, and oreinol derivatives. Usnea is traditionally used around the world against skin infections, upper respiratory and lung infections, and vaginal infections.

It can be dusted as a powder, drank as tea or infusion, used as a wash, bath, soak, douche, or spray. Usnea is also effective in tincture form, 30-60 drops, 4 times daily to boost immunity, 6 times daily to treat an active infection. Drink 2-4 cups of infusion for acute illness. Use 10 drops in an ounce of water and use as a nasal spray to treat sinus infections.

Usnea can sometimes be irritating to delicate mucous membranes of the mouth, nose, and throat, so the tincture should always be diluted in water before using. We walk out into the woods to a big old spruce tree beautifully decorated with long strands of this unique and potent lichen which we gather to make our medicine. Usnea easily absorbs heavy toxic metals and can be potentially toxic, so gather in a clean place.

Usnea Tincture

Shitake Mushroom Lentinus edodes Reishi Ganoderma lucidum, Western reishi/artists conk Ganoderma applanatum Immune activating fungi have been used as allies against disease for millennia. Mysterious mushrooms and fungi are classed in a kingdom all their own. They cannot be called plants, as they are much more primitive, nor are they animal. Fungi actually possess some characteristics of both plant and animal.

There are many common medicinal mushrooms with immune enhancing properties, including maitake, the abundant birch polypores, turkey tails, honey mushrooms, and hens of the woods.

The polypores are commonly given to chemotherapy and radiation patients in Japan, and have been shown to increase survival rates. The body receives deep nourishment from medicinal fungi, as the nutrients and medicinal properties of mushrooms penetrates deep into the bone marrow. So much so, that some have referred to using medicinal mushrooms as herbal bone marrow transplants!

We'll take a deeper look at two of the most widely used medicinal mushrooms, shitake and reishi.

Shitake mushrooms have been used in China for thousands of years to mobilize the immune system to fight off disease. An immunostimulant, shitake increases the activity of the human immune system against any invading organism.

Antiviral, antitumor shitake has been effectively used to treat viral infections, parasites, and cancer. One of its most important constituents, lintinan, has been shown to stimulate immune competent cells, stimulate T-cell production, and increase macrophage activity.

In one study of 23 people with low killer cell activity, and associated fever and fatique for over 6 months, all responded well to taking lintinan, despite not having responded to conventional therapies, including antibiotics and antipyretics.

Studies have shown shitake to be active against viral encephalitis. It also possesses potent anti-tumor activities, and has been shown to prevent metastasis of cancer to the lungs.

Shitake mushrooms are usually added to soups and stews, cooked for about two hours, and then allowed to sit for an additional two hours. Remove the mushrooms before consuming the broth.

Called reishi in Japan, and Ling zhe in China, all the Ganodermas are powerfully immune enhancing, and adaptogens with potent anti cancer properties.

Both sweet and bitter, the Ganodermas are powerful free radical scavengers, eliminating these highly reactive chemicals from the blood stream before they can damage the DNA of healthy cells. Ganodermas are strongly cancer protective, and have been shown to actually help break down and dissolve tumors.

Ganodermas are an excellent addition to the diet of any one who is run down, has been suffering from long term stress, and has low immune function. Either of the Ganodermas effectively increases leukocyte production, promotes lymphatic health, promotes phagocytosis, stimulates T-cells, induces the generation of immunoglobulins, and promotes the multiplication of antibodies.

Scientists from the Tokyo Medical and Dental University demonstrated that the ganoderic acid in these fungi could reduce the cholesterol production in the liver by as much as 95%.

The Ganodermas are heart warming, heart opening, promote serenity, and are said to enhance spiritual powers.

Reishi and artists conk are hard and woody, and are often referred to as shelf mushrooms. They grow on the side of either dead or living trees, and are often found on birch and other hardwoods, or hemlock. Sometimes you will find them growing on the fresh stump of a recently cut or fallen tree, and sometimes on an old stump.

Read the rest here:
Herbs for the Immune System - Blessed Maine

Find your glossary term by first letter:

a form of complementary and alternative medicine that involves inserting thin needles through the skin at specific points on the body to control pain and other symptoms.

written instructions letting others know the type of care you want if you are seriously ill or dying. These include a living will and health care power of attorney.

disorders that involve an immune response in the body. Allergies are reactions to allergens such as plant pollen, other grasses and weeds, certain foods, rubber latex, insect bites, or certain drugs.

tiny glands in the breast that produce milk.

a brain disease that cripples the brain's nerve cells over time and destroys memory and learning. It usually starts in late middle age or old age and gets worse over time. Symptoms include loss of memory, confusion, problems in thinking, and changes in language, behavior, and personality.

clear, slightly yellowish liquid that surrounds the unborn baby (fetus) during pregnancy. It is contained in the amniotic sac.

when the amount of red blood cells or hemoglobin (the substance in the blood that carries oxygen to organs) becomes reduced, causing fatigue that can be severe.

the use of medicine to prevent the feeling of pain or another sensation during surgery or other procedures that might be painful.

a thin or weak spot in an artery that balloons out and can burst.

anticancer drugs that can stop or slow down biochemical reactions in cells.

drugs that inhibit the ability of HIV or other types of retroviruses to multiply in the body.

the body opening from which stool passes from the lower end of the intestine and out of the body.

a form of complementary and alternative medicine in which the scent of essential oils from flowers, herbs, and trees is inhaled to promote health and well-being.

blood vessels that carry oxygen and blood to the heart, brain and other parts of the body.

technology that involves procedures that handle a woman's eggs and a man's sperm to help infertile couples conceive a child.

dry and itchy skin, caused by certain diseases, irritating substances, allergies, or a persons genetic makeup.

a medical condition in kids and adults that makes it hard to sit still, pay attention, and focus on certain tasks.

a condition in which abnormal breast cells are found in either the breast lobules (atypical lobular hyperplasia) or the breast ducts (atypical ductal hyperplasia). Atypical hyperplasia is not cancer. But having it increases breast cancer risk.

blood proteins made by the body's immune system that are meant to neutralize and destroy germs or other foreign substances but instead attack healthy cells of the body.

an immune response by the body against one of its own tissues, cells, or molecules.

disease caused by an immune response against foreign substances in the tissues of one's own body.

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microorganisms that can cause infections.

noncancerous

a type of medication that reduces nerve impulses to the heart and blood vessels. This makes the heart beat slower and with less force. Blood pressure drops and the heart works less hard.

a brown liquid made by the liver. It contains some substances that break up fat for digestion, while other substances are waste products.

when the hemoglobin in a person's blood breaks down, causing a yellowing of the skin and whites of the eyes. It is a temporary condition in newborn infants.

an eating disorder caused by a person being unable to control the need to overeat.

having to do with, or related to, living things.

removal of a small piece of tissue for testing or examination under a microscope.

medical illness that causes unusual shifts in mood, energy, and activity levels. It is also known as manic-depressive illness. A person with bipolar disorder may switch from feeling extremely joyful or excited to feeling extremely sad and hopeless very quickly.

a special place for women to give birth. They have all the required equipment for birthing, but are specially designed for a woman, her partner, and family. Birth centers may be free standing (separate from a hospital) or located within a hospital.

the organ in the human body that stores urine. It is found in the lower part of the abdomen.

fluid in the body made up of plasma, red and white blood cells, and platelets. Blood carries oxygen and nutrients to and waste materials away from all body tissues. In the breast, blood nourishes the breast tissue and provides nutrients needed for milk production.

blood pressure is the force of blood against the walls of arteries. Blood pressure is noted as two numbersthe systolic pressure (as the heart beats) over the diastolic pressure (as the heart relaxes between beats). The numbers are written one above or before the other, with the systolic number on top and the diastolic number on the bottom. For example, a blood pressure reading of 120/80 mmHg (millimeters of mercury) is called 120 over 80.

the transfer of blood or blood products from one person (donor) into another person's bloodstream (recipient). Most times, it is done to replace blood cells or blood products lost through severe bleeding. Blood can be given from two sources, your own blood (autologous blood) or from someone else (donor blood).

how a person feels about how she or he looks.

a measure of body fat based on a person's height and weight.

also known as the intestine, which is a long tube-like organ in the human body that completes digestion or the breaking down of food. The small bowel is the small intestine and the large bowel is the large intestine.

inflammation of the main air passages (bronchi) to your lungs. It causes cough, shortness of breath, and chest tightness.

an eating disorder caused by a person consuming an extreme amount of food all at once followed by self-induced vomiting or other purging.

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a unit of energy-producing potential in food.

a term for diseases in which abnormal cells in the body divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymphatic system, which is a network of tissues that clears infections and keeps body fluids in balance.

compounds such as sugars and starches that occur in food and are broken down to release energy in the body.

disease of the heart and blood vessels.

a sudden loss of motor tone and strength.

cloudy or thick areas in the lens of the eye.

disease of the blood vessels in the brain.

procedure where the baby is delivered through an abdominal incision. Also called cesarean delivery or cesarean birth.

treatment with anticancer drugs.

an alternative medical system that takes a different approach from standard medicine in treating health problems. The goal of chiropractic therapy is to normalize this relationship between your body's structure (mainly the spine) and its function. Chiropractic professionals use a type of hands-on therapy called spinal manipulation or adjustment.

If necessary this test is performed between 10 and 12 weeks of pregnancy and can indicate the same chromosomal abnormalities and genetic disorders as amniocentesis can. It also can detect the baby's sex and risk of spina bifida.

long-lasting, such as a chronic illness or chronic disease.

a complex disorder characterized by extreme fatigue that lasts six months or longer, and does not improve with rest or is worsened by physical or mental activity. Other symptoms can include weakness, muscle pain, impaired memory and/or mental concentration, and insomnia. The cause is unknown.

birth defects that affect the upper lip and the hard and soft palates of the mouth. Features range from a small notch in the lip to a complete fissure or groove, extending into the roof of the month and nose. These features may occur separately or together.

an external female sex organ located near the top of the inner labia of the vagina. The clitoris is very sensitive to the touch, and for most women it is a center of sexual pleasure.

to force someone to do something that they do not want to do.

a diagnostic procedure in which a flexible tube with a light source in inserted into the colon (large intestine or large bowel) through the anus to view all sections of the colon for abnormalities.

thick, yellowish fluid secreted from breast during pregnancy, and the first few days after childbirth before the onset of mature breast milk. Also called first milk, it provides nutrients and protection against infectious diseases.

abnormalities of the heart's structure and function caused by abnormal or disordered heart development before birth.

a type of body tissue that supports other tissues and binds them together. Connective tissue provides support in the breast.

infrequent or hard stools or difficulty passing stools.

transmitted by direct or indirect contact.

usually has a master's degree in Counseling and has completed a supervised internship.

an ongoing condition that causes inflammation of the digestive tract, also called the GI tract. It can affect any part of the GI tract from the mouth to the anus. It often affects the lower part of the small intestine, causing pain and diarrhea.

one of the most common serious genetic (inherited) diseases. One out of every 400 couples is at risk for having children with CF. CF causes the body to make abnormal secretions leading to mucous build-up. CF mucous build-up can impair organs such as the pancreas, the intestine and the lungs.

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impairs the vitality and strength of a person.

medications that treat cough and stuffy nose by shrinking swollen membranes in the nose and making it easier to breath.

excessive loss of body water that the body needs to carry on normal functions at an optimal level. Signs include increasing thirst, dry mouth, weakness or lightheadedness (particularly if worse on standing), and a darkening of the urine or a decrease in urination.

when a person believes something that is not true and that person keeps the belief even though there is strong evidence against it. Delusions can be the result of brain injury or mental illness.

a square, thin piece of latex that can be placed over the anus or the vagina before oral sex.

term used to describe an emotional state involving sadness, lack of energy and low self-esteem.

medical treatment used when kidneys fail. Special equipment filters the blood to rid the body of harmful wastes, salt, and extra water.

tube through which food passes and is digested, and wastes are eliminated. The digestive tract runs from the mouth to the anus and includes the esophagus, stomach, and intestines.

a physical or mental impairment that interferes with or prevents normal achievement in a particular function.

a lab test in which a patient's DNA is tested. DNA is a molecule that has a person's genetic information and is found in every cell in a person's body.

Down syndrome is the most frequent genetic cause for mild to moderate mental retardation and related medical problems. It is caused by a chromosomal abnormality. For an unknown reason, a change in cell growth results in 47 instead of the usual 46 chromosomes. This extra chromosome changes the orderly development of the body and brain.

a condition in which abnormal cells are found in the lining of breast ducts. These cells have not spread outside the duct to the surrounding breast tissue. DCIS is not cancer. But some cases of DCIS become breast cancer over time, so its important to get treatment for DCIS.

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an external, noninvasive test that records the electrical activity of the heart.

a period during pregnancy where the baby has rapid growth, and the main external features begin to take form.

a condition caused by damage to the air sacs in the lungs. This damage keeps the body from getting enough oxygen. Symptoms include trouble breathing, cough, and trouble exercising for more than brief periods. Emphysema is usually caused by smoking.

a diagnostic procedure in which a thin, flexible tube is introduced through the mouth or rectum to view parts of the digestive tract.

during labor a woman may be offered an epidural, where a needle is inserted into the epidural space at the end of the spine, to numb the lower body and reduce pain. This allows a woman to have more energy and strength for the end stage of labor, when it is time to push the baby out of the birth canal.

inability to achieve and keep a penile erection.

tube that connects the throat with the stomach.

when someone exposes him/herself in public

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a federal regulation that allows eligible employees to take up to 12 work weeks of unpaid leave during any 12 month period for the serious health condition of the employee, parent, spouse or child, or for pregnancy or care of a newborn child, or for adoption or foster care of a child.

a rare, inherited blood disorder that leads to bone marrow failure. FA causes your bone marrow to stop making enough new blood cells for your body to work normally. The risk for some cancers is much greater for people with FA.

a source of energy used by the body to make substances it needs. Fat helps your body absorb certain vitamins from food. Some fats are better for your health than others. To help prevent heart disease and stroke, most of the fats you eat should be monounsaturated (mon-oh-uhn-SACH-uh-ray-tid) and polyunsaturated (pol-ee-uhn-SACH-uh-ray-tid) fats.

a feeling of lack of energy, weariness or tiredness.

a barrier form of birth control that is worn by the woman inside her vagina. It is made of thin, flexible, manmade rubber. It keeps sperm from getting into her body.

a term used to describe the full range of harmful effects that can occur when a fetus is exposed to alcohol.

body temperature is raised above normal and is usually a sign of infection or illness.

a disorder that causes aches and pain all over the body, and involves tender points on specific places on the neck, shoulders, back, hips, arms, and legs that hurt when pressure is put on them.

each month, an egg develops inside the ovary in a fluid filled pocket called a follicle. This follicle releases the egg into the fallopian tube.

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Glossary Index | womenshealth.gov

Mary Shomon

Acquired immunodeficiency syndrome (AIDS):A life-threatening disease caused by a virus and characterized by breakdown of the body's immune defenses.

Active immunity:Immunity produced by the body in response to stimulation by a disease-causing organism or a vaccine.

Agammaglobulinemia:An almost total lack of immunoglobulins, or antibodies.

Allergen:Any substance that causes an allergy.

Allergy:An inappropriate and harmful response of the immune system to normally harmless substances.

Anaphylactic shock:A life-threatening allergic reaction characterized by a swelling of body tissues including the throat, difficulty in breathing, and a sudden fall in blood pressure.

Anergy:A state of unresponsiveness, induced when the T cell's antigen receptor is stimulated, that effectively freezes T cell responses pending a "second signal" from the antigen-presenting cell (co-stimulation).

Antibody:A soluble protein molecule produced and secreted by B cells in response to an antigen, which is capable of binding to that specific antigen.

Antibody-dependent cell-mediated cytotoxicity (ADCC):An immune response in which antibody, by coating target cells, makes them vulnerable to attack by immune cells.

Antigen:Any substance that, when introduced into the body, is recognized by the immune system.

Antigen-presenting cells:B cells, cells of the monocyte lineage (including macrophages as well as dendritic cells), and various other body cells that "present" antigen in a form that T cells can recognize.

Antinuclear antibody (ANA):An autoantibody directed against a substance in the cell's nucleus.

Antiserum:Serum that contains antibodies.

Antitoxins:Antibodies that interlock with and inactivate toxins produced by certain bacteria.

Appendix:Lymphoid organ in the intestine.

Attenuated:Weakened; no longer infectious.

Autoantibody:An antibody that reacts against a person's own tissue.

Autoimmune disease:A disease that results when the immune system mistakenly attacks the body's own tissues. Rheumatoid arthritis and systemic lupus erythematosus are autoimmune diseases.

Bacterium:A microscopic organism composed of a single cell. Many but no all bacteria cause disease.

Basophil:A white blood cell that contributes to inflammatory reactions. Along with mast cells, basophils are responsible for the symptoms of allergy.

B cells:Small white blood cells crucial to the immune defenses. Also known as B lymphocytes, they are derived from bone marrow and develop into plasma cells that are the source of antibodies.

Biological response modifiers:Substances, either natural or synthesized, that boost, direct, or restore normal immune defenses. BRMs include interferons, interleukins, thymus hormones, and monoclonal antibodies.

Biotechnology:The use of living organisms or their products to make or modify a substance. Biotechnology includes recombinant DNA techniques (genetic engineering) and hybridoma technology.

Bone marrow:Soft tissue located in the cavities of the bones. The bone marrow is the source of all blood cells.

Cellular immunity:Immune protection provided by the direct action of immune cells (as distinct from soluble molecules such as antibodies).

Chromosomes:Physical structures in the cell's nucleus that house the genes. Each human cell has 23 pairs of chromosomes.

Clone:(n.)A group of genetically identical cells or organisms descended from a single common ancestor; (v.) to reproduce multiple identical copies.

Complement:A complex series of blood proteins whose action "complements" the work of antibodies. Complement destroys bacteria, produces inflammation, and regulates immune reactions.

Complement cascade:A precise sequence of events usually triggered by an antigen-antibody complex, in which each component of the complement system is activated in turn.

Constant region:That part of an antibody's structure that is characteristic for each antibody class.

Co-Stimulation:The delivery of a second signal from an antigen-presenting cell to a T cell. The second signal rescues the activated T cell from anergy, allowing it to produce the lymphokines necessary for the growth of additional T cells.

Cytokines:Powerful chemical substances secreted by cells. Cytokines include lymphokines produced by lymphocytes and monokines produced by monocytes and macrophages.

Cytotoxic T cells:A subset of T lymphocytes that can kill body cells infected by viruses or transformed by cancer.

Dendritic cells:White blood cells found in the spleen and other lymphoid organs. Dendritic cells typically use threadlike tentacles to enmesh antigen, which they present to T cells.

DNA (deoxyribonucleic acid):Nucleic acid that is found in the cell nucleus and that is the carrier of genetic information.

Enzyme:A protein, produced by living cells, that promotes the chemical processes of life without itself being altered.

Eosinophil:A white blood cell that contains granules filled with chemicals damaging to parasites, and enzymes that damp down inflammatory reactions.

Epitope:A unique shape or marker carried on an antigen's surface, which triggers a corresponding antibody response.

Fungus:Member of a class of relatively primitive vegetable organism. Fungi include mushrooms, yeasts, rusts, molds, and smuts.

Gene:A unit of genetic material (DNA) that carries the directions a cell uses to perform a specific function, such as making a given protein.

Graft-versus-host disease (GVHD):A life-threatening reaction in which transplanted immunocompetent cells attack the tissues of the recipient.

Granulocytes:White blood cells filled with granules containing potent chemicals that allow the cells to digest microorganisms, or to produce inflammatory reactions. Neutrophils, eosinophils, and basophils are examples of granulocytes.

Helper T cells:A subset of T cells that typically carry the T4 marker and are essential for turning on antibody production, activating cytotoxic T cells, and initiating many other immune responses.

Hematopoiesis:The formation and development of blood cells, usually takes place in the bone marrow.

Histocompatibility testing:A method of matching the self antigens (HLA) on the tissues of a transplant donor with those of the recipient. The closer the match, the better the chance that the transplant will take.

HIV (human immunodeficiency virus):The virus that causes AIDS.

Human leukocyte antigens (HLA):Protein in markers of self used in histocompatibility testing. Some HLA types also correlate with certain autoimmune diseases.

Humoral immunity:Immune protection provided by soluble factors such as antibodies, which circulate in the body's fluids or "humors," primarily serum and lymph.

Hybridoma:A hybrid cell created by fusing a B lymphocyte with a long-lived neoplastic plasma cell, or a T lymphocyte with a lymphoma cell. A B-cell hybridoma secretes a single specific antibody.

Hypogammaglobulinemia:Abno rmally low levels of immunoglobulins.

Idiotypes:The unique and characteristic parts of an antibody's variable region, which can themselves serve as antigens.

Immune complex:A cluster of interlocking antigens and antibodies.

Immune response:The reactions of the immune system to foreign substances.

Immunoassay:A test using antibodies to identify and quantify substances. Often the antibody is linked to a marker such as a fluorescent molecule, a radioactive molecule, or an enzyme.

Immunocompetent:Capable of developing an immune response.

Immunoglobulins:A family of large protein molecules, also known as antibodies.

Immunosuppression:Reduction of the immune responses, for instance by giving drugs to prevent transplant rejection.

Immunotoxin:A monoclonal antibody linked to a natural toxin, a toxic drug, or a radioactive substance.

Inflammatory response:Redness, warmth, swelling, pain, and loss of function produced in response to infection, as the result of increased flood flow and an influx of immune cells and secretions.

Interleukins:A major group of lymphokines and monokines.

Kupffer cells:Specialized macrophages in the liver.

LAK cells:Lymphocytes transformed in the laboratory into lymphokine-activated killer cells, which attack tumor cells.

Langerhans cells:Dendritic cells in the skin that pick up antigen and transport it to lymph nodes.

Leukocytes:All white blood cells.

Lymph:A transparent, slightly yellow fluid that carries lymphocytes, bathes the body tissues, and drains into the lymphatic vessels.

Lymphatic vessels:A bodywide network of channels, similar to the blood vessels, which transport lymph to the immune organs and into the bloodstream.

Lymph nodes:Small bean-shaped organs of the immune system, distributed widely throughout the body and linked by lymphatic vessels. Lymph nodes are garrisons of B, T, and other immune cells.

Lymphocytes:Small white blood cells produced in the lymphoid organs and paramount in the immune defenses.

Lymphoid organs:The organs of the immune system, where lymphocytes develop and congregate. They include the bone marrow, thymus, lymph nodes, spleen, and various other clusters of lymphoid tissue. The blood vessels and lymphatic vessels can also be considered lymphoid organs.

Lymphokines:Powerful chemical substances secreted by lymphocytes. These soluble molecules help direct and regulate the immune responses.

Macrophage:A large and versatile immune cell that acts as a microbe-devouring phagocyte, an antigen-presenting cell, and an important source of immune secretions.

Major histocompatibility complex (MHC):A group of genes that controls several aspects of the immune response. MHC genes code for self markers on all body cells.

Mast cell:A granule-containing cell found in tissue. The contents of mast cells, along with those of basophils, are responsible for the symptoms of allergy.

Microbes:Minute living organisms, including bacteria, viruses, fungi and protozoa.

Microorganisms:Microscopic plants or animals.

Molecule:The smallest amount of a specific chemical substance that can exist alone. (The break a molecule down into its constituent atoms is to change its character. A molecule of water, for instance, reverts to oxygen and hydrogen.)

Monoclonal antibodies:Antibodies produced by a single cell or its identical progeny, specific for a given antigen. As a tool for binding to specific protein molecules, monoclonal antibodies are invaluable in research, medicine, and industry.

Monocyte:A large phagocytic white blood cell which, when it enters tissue, develops into a macrophage.

Monokines:Powerful chemical substances secreted by monocytes and macrophages. These soluble molecules help direct and regulate the immune responses.

Natural killer (NK) cells:Large granule-filled lymphocytes that take on tumor cells and infected body cells. They are known as "natural" killers because they attack without first having to recognize specific antigens.

Neutrophil:A white blood cell that is an abundant and important phagocyte.

Nucleic acids:Large, naturally occurring molecules composed of chemical building blocks known as nucleotides. There are two kinds of nucleic acids, DNA and RNA.

OKT3:A monoclonal antibody that targets mature T cells.

Opportunistic infection:An infection in an immunosuppressed person caused by an organism that does not usually trouble people with healthy immune systems.

Opsonize:To coat an organism with antibodies or a complement protein so as to make it palatable to phagocytes.

Organism:An individual living thing.

Parasite:A plant or animal that lives, grows and feeds on or within another living organism.

Passive immunity:Immunity resulting from the transfer of antibodies or antiserum produced by another individual.

Peyer's patches:A collection of lymphoid tissues in the intestinal tract.

Phagocytes:Large white blood cells that contribute to the immune defenses by ingesting microbes or other cells and foreign particles.

Plasma cells:Large antibody-producing cells that develop from B cells.

Platelets:Granule-containing cellular fragments critical for blood clotting and sealing off wounds. Platelets also contribute to the immune response.

Polymorphs:Short for polymorphonuclear leukocytes or granulocytes.

Proteins:Organic compounds made up of amino acids. Proteins are one of the major constituents of plant and animal cells.

Protozoa:A group of one-celled animals, a few of which cause human disease (including malaria and sleeping sickness).

Rheumatoid factor:An autoantibody found in the serum of most persons with rheumatoid arthritis.

RNA (ribonucleic acid):A nucleic acid that is found in the cytoplasm and also in the nucleus of some cells. One function of RNA is to direct the synthesis of proteins.

Scavenger cells:Any of a diverse group of cells that have the capacity to engulf and destroy foreign material, dead tissues, or other cells.

SCID mouse:A laboratory animal that, lacking an enzyme necessary to fashion an immune system of its own, can be turned into a model of the human immune system when injected with human cells or tissues.

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A Comprehensive Guide to Understanding the Immune System

The immune system is the system of specialized cells and organs that protects an organism from outside biological influences (though in a broad sense, almost every organ has a protective functionfor example, the tight seal of the skin or the acidic environment of the stomach).

When the immune system is functioning properly, it protects the body against bacteria and viral infections and destroys cancer cells and foreign substances. If the immune system weakens, its ability to defend the body also weakens, allowing pathogens (infectious agents), including viruses that cause common colds and flu, to survive and flourish in the body. Because the immune system also performs surveillance of tumor cells, immune suppression has been reported to increase the risk of certain types of cancer.

The complex coordination of the immune system is stunning. It is capable of recognizing millions of invaders and neutralizing their attacks, and yet at the same time it allows helpful, symbiotic bacteria, such as E. coli, to become established within the human body. From the time of the initial invasion of a foreign element until its removal, the entire immune systemincluding diverse types of white blood cells, each with a different responsibilityharmoniously functions together in recognizing, attacking, and destroying substances identified as foreign.

The immune system is often divided into two sections:

Another way of categorizing this is "nonspecific defenses" (skin, mucous membranes, phagocytes, fever, interferons, cilia, and stomach acid) and "specific defenses" (the cell-mediated and the humoral systems, both of which attack specific pathogens).

The adaptive immune system, also called the "acquired immune system, and "specific immune system," ensures that animals that survive an initial infection by a pathogen are generally immune to further illness caused by that same pathogen. The adaptive immune system is based on dedicated immune cells termed leukocytes (white blood cells).

The basis of specific immunity lies in the capacity of immune cells to distinguish between proteins produced by the body's own cells ("self" antigenthose of the original organism), and proteins produced by invaders or cells under control of a virus ("non-self" antigenor, what is not recognized as the original organism). This distinction is made via T-Cell Receptors (TCR) or B-Cell Receptors (BCR). For these receptors to be efficient they must be produced in thousands of configurations; this way they are able to distinguish between many different invader proteins.

This immense diversity of receptors would not fit in the genome of a cell, and millions of genes, one for each type of possible receptor, would be impractical. Instead, there are a few families of genes, each one having a slightly different modification. Through a special process, unique to cells of jawed vertebrates (Gnathostomata), the genes in these T-cell and B-cell lymphocytes recombine, one from each family, arbitrarily into a single gene.

This way, for example, each antibody or BCR of B lymphocytes has six portions, and is created from two genes unique to this lymphocyte, created by the recombination (union) of a random gene from each family. If there are 6 families, with 50, 30, 9, 40, and 5 members, the total possible number of antibodies is 50x30x6x9x40x5 = 16 million. On top of this there are other complex processes that increase the diversity of BCR or TCR even more, by mutation of the genes in question. The variability of antibodies is practically limitless, and the immune system creates antibodies for any molecule, even artificial molecules that do not exist in nature.

Many TCR and BCR created this way will react with their own peptides. One of the functions of the thymus and bone marrow is to hold young lymphocytes until it is possible to determine which ones react to molecules of the organism itself. This is done by specialized cells in these organs that present the young lymphocytes with molecules produced by them (and effectively the body). All the lymphocytes that react to them are destroyed, and only those that show themselves to be indifferent to the body are released into the bloodstream.

The lymphocytes that do not react to the body number in the millions, each with millions of possible configurations of receptors, each with a receptor for different parts of each microbial protein possible. The vast majority of lymphocytes never find a protein that its receptor is specified for, those few that do find one are stimulated to reproduce. Effective cells are generated with the specific receptor and memory cells. These memory cells are quiescent, they have long lives and are capable of identifying this antigen some time later, multiplying themselves quickly and rapidly responding to future infections.

In many species, the adaptive immune system can be divided into two major sections, the humoral immune system and the cell-mediated immune system.

The humoral immune system acts against bacteria and viruses in the body liquids (e.g., blood) by means of proteins, called immunoglobulins (also known as antibodies), which are produced by B cells. B cells are lymphocytes, with the "B" standing for the bursa of Fabricius, an organ unique to birds, where avian B cells mature. (It does not stand for bone marrow, where B cells are produced in all other vertebrates except for rabbits. B cells were original observed in studies done on immunity in chickens.)

Secreted antibodies bind to antigens on the surfaces of invading microbes (such as viruses or bacteria), which flags them for destruction. An antigen is any substance that causes the immune system to produce antibodies.

Humoral immunity refers to antibody production and all the accessory processes that accompany it: Th2 (T-helper 2 cells) activation and cytokine production (cytokines are proteins that affect the interaction between cells); germinal center formation and isotype switching (switching a specific region of the antibody); and affinity maturation and memory cell generation (memory cell generation has to do with the ability for a body to "remember" a pathogen by producing antibodies specifically targeted for it). Humoral immunity also refers to the effector functions of antibodies, which include pathogen and toxin neutralization, classical complement activation, and opsonin promotion of phagocytosis and pathogen elimination.

The human body has the ability to form millions of different types of B cells each day, and each type has a unique receptor protein, referred to as the B cell receptor (BCR), on its membrane that will bind to one particular antigen. At any one time in the human body there are B cells circulating in the blood and lymph, but are not producing antibodies. Once a B cell encounters its cognate antigen and receives an additional signal from a helper T cell, it can further differentiate into one of two types of B cells.

B cells need two signals to initiate activation. Most antigens are T-dependent, meaning T cell help is required for maximum antibody production. With a T-dependent antigen, the first signal comes from antigen cross linking BCR (B cell receptor) and the second from the Th2 cell. T-dependent antigens present peptides on B cell Class II MHC proteins to Th2 cells. This triggers B cell proliferation and differentiation into plasma cells. Isotype switching to IgG, IgA, and IgE and memory cell generation occur in response to T-dependent antigens.

Some antigens are T-independent, meaning they can deliver both the antigen and the second signal to the B cell. Mice without a thymus (nude or athymic mice) can respond to T-independent antigens. Many bacteria have repeating carbohydrate epitopes that stimulate B cells to respond with IgM synthesis in the absence of T cell help.

T-dependent responses require that B cells and their Th2 cells respond to epitopes on the same antigen. T and B cell epitopes are not necessarily identical. (Once virus-infected cells have been killed and unassembled virus proteins released, B cells specific for internal proteins can also be activated to make opsonizing antibodies to those proteins.) Attaching a carbohydrate to a protein can convert the carbohydrate into a T-dependent antigen; the carbohydrate-specific B cell internalizes the complex and presents peptides to Th2 cells, which in turn activate the B cell to make antibodies specific for the carbohydrate.

An antibody is a large Y-shaped protein used to identify and neutralize foreign objects like bacteria and viruses. Production of antibodies and associated processes constitutes the humoral immune system. Each antibody recognizes a specific antigen unique to its target. This is because at the two tips of its "Y," it has structures akin to locks. Every lock only has one key, in this case, its own antigen. When the key is inserted into the lock, the antibody activates, tagging or neutralizing its target. The production of antibodies is the main function of the humoral immune system.

Immunoglobulins are glycoproteins in the immunoglobulin superfamily that function as antibodies. The terms antibody and immunoglobulin are often used interchangeably. They are found in the blood and tissue fluids, as well as many secretions. In structure, they are globulins (in the -region of protein electrophoresis). They are synthesized and secreted by plasma cells that are derived from the B cells of the immune system. B cells are activated upon binding to their specific antigen and differentiate into plasma cells. In some cases, the interaction of the B cell with a T helper cell is also necessary.

In humans, there are five types: IgA, IgD, IgE, IgG, and IgM. (Ig stands for immunoglobulin.). This is according to differences in their heavy chain constant domains. (The isotypes are also defined with light chains, but they do not define classes, so they are often neglected.) Other immune cells partner with antibodies to eliminate pathogens depending on which IgG, IgA, IgM, IgD, and IgE constant binding domain receptors it can express on its surface.

The antibodies that a single B lymphocyte produces can differ in their heavy chain, and the B cell often expresses different classes of antibodies at the same time. However, they are identical in their specificity for antigen, conferred by their variable region. To achieve the large number of specificities the body needs to protect itself against many different foreign antigens, it must produce millions of B lymphoyctes. In order to produce such a diversity of antigen binding sites for each possible antigen, the immune system would require many more genes than exist in the genome. It was Susumu Tonegawa who showed in 1976 that portions of the genome in B lymphocytes can recombine to form all the variation seen in the antibodies and more. Tonegawa won the Nobel Prize in Physiology or Medicine in 1987 for his discovery.

The cell-mediated immune system, the second main mechanism of the adaptive immune system, destroys virus-infected cells (among other duties) with T cells, also called "T lymphocytes." ("T" stands for thymus, where their final stage of development occurs.)

Cell-mediated immunity is an immune response that does not involve antibodies but rather involves the activation of macrophages and natural killer cells, the production of antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen. Cellular immunity protects the body by:

Cell-mediated immunity is directed primarily at microbes that survive in phagocytes and microbes that infect non-phagocytic cells. It is most effective in removing virus-infected cells, but also participates in defending against fungi, protozoans, cancers, and intracellular bacteria. It also plays a major role in transplant rejection.

There are two major types of T cells:

In addition, there are regulatory T cells (Treg cells) which are important in regulating cell-mediated immunity.

The adaptive immune system could take days or weeks after an initial infection to have an effect. However, most organisms are under constant assault from pathogens that must be kept in check by the faster-acting innate immune system. Innate immunity, or non-specific defense, defends against pathogens by rapid responses coordinated through chemical or physical barriers or "innate" receptors that recognize a wide spectrum of conserved pathogenic components.

In evolutionary time, it appears that the adaptive immune system developed abruptly in jawed fish. Prior to jawed fish, there is no evidence of adaptive immunity, and animals therefore relied only on their innate immunity. Plants, on the other hand, rely on secondary metabolites (chemical compounds in organisms that are not directly involved in the normal growth, development, or reproduction of organisms) to defend themselves against fungal and viral pathogens as well as insect herbivory. Plant secondary metabolites are derived through vast arrays of plant biosynthetic pathways not needed directly for plant survival, hence why they are named secondary. Plant secondary metabolism should not be confused with innate or adaptive immunity as they evolved along an entirely different evolutionary lineages and rely on entirely different signal cues, pathways, and responses.

The innate immune system, when activated, has a wide array of effector cells and mechanisms. There are several different types of phagocytic cells, which ingest and destroy invading pathogens. The most common phagocytes are neutrophils, macrophages, and dendritic cells. Another cell type, natural killer cells, are especially adept at destroying cells infected with viruses. Another component of the innate immune system is known as the complement system. Complement proteins are normally inactive components of the blood. However, when activated by the recognition of a pathogen or antibody, the various proteins recruit inflammatory cells, coat pathogens to make them more easily phagocytosed, and make destructive pores in the surfaces of pathogens.

The first-line defense includes barriers to infection, such as skin, the mucous coating of the gut, and airways. These physically prevent the interaction between the host and the pathogen. Pathogens that penetrate these barriers encounter constitutively expressed (constantly expressed) anti-microbial molecules (e.g., lysozymes) that restrict the infection.

In addition to the usual defense, the stomach secretes gastric acid, which, in addition to aiding digestive enzymes in the stomach to work on food, prevents bacterial colonization by most pathogens.

The second-line defense includes phagocytic cells (macrophages and neutrophil granulocytes) that can engulf (phagocytose) foreign substances. Macrophages are thought to mature continuously from circulating monocytes.

Phagocytosis involves chemotaxis, where phagocytic cells are attracted to microorganisms by means of chemotactic chemicals such as microbial products, complement, damaged cells, and white blood cell fragments. Chemotaxis is followed by adhesion, where the phagocyte sticks to the microorganism. Adhesion is enhanced by opsonization, where proteins like opsonins are coated on the surface of the bacterium. This is followed by ingestion, in which the phagocyte extends projections, forming pseudopods that engulf the foreign organism. Finally, the bacterium is digested by the enzymes in the lysosome, exposing it to reactive oxygen species and proteases.

In addition, anti-microbial proteins may be activated if a pathogen passes through the barrier offered by skin. There are several classes of antimicrobial proteins, such as acute phase proteins (C-reactive protein, for example, enhances phagocytosis and activates complement when it binds itself to the C-protein of S. pneumoniae ), lysozyme, and the complement system.

The complement system is a very complex group of serum proteins, which is activated in a cascade fashion. Three different pathways are involved in complement activation:

A cascade of protein activity follows complement activation; this cascade can result in a variety of effects, including opsonization of the pathogen, destruction of the pathogen by the formation and activation of the membrane attack complex, and inflammation.

Interferons are also anti-microbial proteins. These molecules are proteins that are secreted by virus-infected cells. These proteins then diffuse rapidly to neighboring cells, inducing the cells to inhibit the spread of the viral infection. Essentially, these anti-microbial proteins act to prevent the cell-to-cell proliferation of viruses.

Earlier studies of innate immunity utilized model organisms that lack adaptive immunity, such as the plant Arabidopsis thaliana, the fly Drosophila melanogaster, and the worm Caenorhabditis elegans. Advances have since been made in the field of innate immunology with the discovery of toll-like receptors (TLRs) and the intracellular nucleotide-binding site leucine-rich repeat proteins (NODs). NODs are receptors in mammal cells that are responsible for a large proportion of the innate immune recognition of pathogens.

In 1989, prior to the discovery of mammalian TLRs, Charles Janeway conceptualized and proposed that evolutionarily conserved features of infectious organisms were detected by the immune system through a set of specialized receptors, which he termed pathogen-associated molecular patterns (PAMPs) and pattern recognition receptors (PRRs), respectively. This insight was only fully appreciated after the discovery of TLRs by the Janeway lab in 1997. The TLRs now comprise the largest family of innate immune receptors (or PRRs). Janeways hypothesis has come to be known as the "stranger model" and substantial debate in the field persists to this day as to whether or not the concept of PAMPs and PRRs, as described by Janeway, is truly suitable to describe the mechanisms of innate immunity. The competing "danger model" was proposed in 1994 by Polly Matzinger and argues against the focus of the stranger model on microbial derived signals, suggesting instead that endogenous danger/alarm signals from distressed tissues serve as the principle purveyors of innate immune responses.

Both models are supported in the later literature, with discoveries that substances of both microbial and non-microbial sources are able to stimulate innate immune responses, which has led to increasing awareness that perhaps a blend of the two models would best serve to describe the currently known mechanisms governing innate immunity.

Splitting the immune system into innate and adaptive systems simplifies discussions of immunology. However, the systems actually are quite intertwined in a number of important respects.

One important example is the mechanisms of "antigen presentation." After they leave the thymus, T cells require activation to proliferate and differentiate into cytotoxic ("killer") T cells (CTLs). Activation is provided by antigen-presenting cells (APCs), a major category of which are the dendritic cells. These cells are part of the innate immune system.

Activation occurs when a dendritic cell simultaneously binds itself to a T "helper" cell's antigen receptor and to its CD28 receptor, which provides the "second signal" needed for DC activation. This signal is a means by which the dendritic cell conveys that the antigen is indeed dangerous, and that the next encountered T "killer" cells need to be activated. This mechanism is based on antigen-danger evaluation by the T cells that belong to the adaptive immune system. But the dendritic cells are often directly activated by engaging their toll-like receptors, getting their "second signal" directly from the antigen. In this way, they actually recognize in "first person" the danger, and direct the T killer attack. In this respect, the innate immune system therefore plays a critical role in the activation of the adaptive immune system.

Adjuvants, or chemicals that stimulate an immune response, provide artificially this "second signal" in procedures when an antigen that would not normally raise an immune response is artificially introduced into a host. With the adjuvant, the response is much more robust. Historically, a commonly-used formula is Freund's Complete Adjuvant, an emulsion of oil and mycobacterium. It was later discovered that toll-like receptors, expressed on innate immune cells, are critical in the activation of adaptive immunity.

Many factors can contribute to the general weakening of the immune system:

Despite high hopes, there are no medications that directly increase the activity of the immune system. Various forms of medication that activate the immune system may cause autoimmune disorders.

Suppression of the immune system is often used to control autoimmune disorders or inflammation when this causes excessive tissue damage, and to prevent transplant rejection after an organ transplant. Commonly used immunosuppressants include glucocorticoids, azathioprine, methotrexate, ciclosporin, cyclophosphamide, and mercaptopurine. In organ transplants, ciclosporin, tacrolimus, mycophenolate mofetil, and various others are used to prevent organ rejection through selective T cell inhibition.

The most important function of the human immune system occurs at the cellular level of the blood and tissues. The lymphatic and blood circulation systems are highways for specialized white blood cells to travel around the body. Each white blood cell type (B cells, T cells, natural killer cells, and macrophages) has a different responsibility, but all function together with the primary objective of recognizing, attacking, and destroying bacteria, viruses, cancer cells, and all substances seen as foreign. Without this coordinated effort, a person would not be able to survive more than a few days before succumbing to overwhelming infection.

Infections set off an alarm that alerts the immune system to bring out its defensive weapons. Natural killer cells and macrophages rush to the scene to consume and digest infected cells. If the first line of defense fails to control the threat, antibodies, produced by the B cells, upon the order of T helper cells, are custom-designed to hone in on the invader.

Many disorders of the human immune system fall into two broad categories that are characterized by:

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Immune system - New World Encyclopedia

The innate immune system, also known as the nonspecific immune system,[1] is an important subsystem of the overall immune system that comprises the cells and mechanisms that defend the host from infection by other organisms. The cells of the innate system recognize and respond to pathogens in a generic way, but, unlike the adaptive immune system (which is found only in vertebrates), it does not confer long-lasting or protective immunity to the host.[2] Innate immune systems provide immediate defense against infection, and are found in all classes of plant and animal life. They include both humoral immunity components and cell-mediated immunity components.

The innate immune system is an evolutionarily older defense strategy, and is the dominant immune system found in plants, fungi, insects, and primitive multicellular organisms.[3]

The major functions of the vertebrate innate immune system include:

Anatomical barriers include physical, chemical and biological barriers. The epithelial surfaces form a physical barrier that is impermeable to most infectious agents, acting as the first line of defense against invading organisms.[4]Desquamation of skin epithelium also helps remove bacteria and other infectious agents that have adhered to the epithelial surfaces. Lack of blood vessels and inability of the epidermis to retain moisture, presence of sebaceous glands in the dermis provides an environment unsuitable for the survival of microbes.[4] In the gastrointestinal and respiratory tract, movement due to peristalsis or cilia, respectively, helps remove infectious agents.[4] Also, mucus traps infectious agents.[4] The gut flora can prevent the colonization of pathogenic bacteria by secreting toxic substances or by competing with pathogenic bacteria for nutrients or attachment to cell surfaces.[4] The flushing action of tears and saliva helps prevent infection of the eyes and mouth.[4]

Inflammation is one of the first responses of the immune system to infection or irritation. Inflammation is stimulated by chemical factors released by injured cells and serves to establish a physical barrier against the spread of infection, and to promote healing of any damaged tissue following the clearance of pathogens.[5]

The process of acute inflammation is initiated by cells already present in all tissues, mainly resident macrophages, dendritic cells, histiocytes, Kupffer cells, and mastocytes. These cells present receptors, contained on the surface or within the cell, named pattern recognition receptors (PRRs), which recognise molecules that are broadly shared by pathogens but distinguishable from host molecules, collectively referred to as pathogen-associated molecular patterns (PAMPs). At the onset of an infection, burn, or other injuries, these cells undergo activation (one of their PRRs recognizes a PAMP) and release inflammatory mediators responsible for the clinical signs of inflammation.

Chemical factors produced during inflammation (histamine, bradykinin, serotonin, leukotrienes, and prostaglandins) sensitize pain receptors, cause vasodilation of the blood vessels at the scene, and attract phagocytes, especially neutrophils.[5] Neutrophils then trigger other parts of the immune system by releasing factors that summon other leukocytes and lymphocytes. Cytokines produced by macrophages and other cells of the innate immune system mediate the inflammatory response. These cytokines include TNF, HMGB1, and IL-1.[6]

The inflammatory response is characterized by the following symptoms:

The complement system is a biochemical cascade of the immune system that helps, or complements, the ability of antibodies to clear pathogens or mark them for destruction by other cells. The cascade is composed of many plasma proteins, synthesised in the liver, primarily by hepatocytes. The proteins work together to:

Elements of the complement cascade can be found in many nonmammalian species including plants, birds, fish, and some species of invertebrates.[7]

All white blood cells (WBC) are known as leukocytes. Leukocytes are different from other cells of the body in that they are not tightly associated with a particular organ or tissue; thus, they function similar to independent, single-cell organisms. Leukocytes are able to move freely and interact with and capture cellular debris, foreign particles, or invading microorganisms. Unlike many other cells in the body, most innate immune leukocytes cannot divide or reproduce on their own, but are the products of multipotent hematopoietic stem cells present in the bone marrow.[2]

The innate leukocytes include: Natural killer cells, mast cells, eosinophils, basophils; and the phagocytic cells including macrophages, neutrophils, and dendritic cells, and function within the immune system by identifying and eliminating pathogens that might cause infection.[3]

Mast cells are a type of innate immune cell that reside in connective tissue and in the mucous membranes. They are intimately associated with wound healing and defense against pathogens, but are also often associated with allergy and anaphylaxis.[5] When activated, mast cells rapidly release characteristic granules, rich in histamine and heparin, along with various hormonal mediators, and chemokines, or chemotactic cytokines into the environment. Histamine dilates blood vessels, causing the characteristic signs of inflammation, and recruits neutrophils and macrophages.[5]

The word 'phagocyte' literally means 'eating cell'. These are immune cells that engulf, i.e. phagocytose, pathogens or particles. To engulf a particle or pathogen, a phagocyte extends portions of its plasma membrane, wrapping the membrane around the particle until it is enveloped (i.e., the particle is now inside the cell). Once inside the cell, the invading pathogen is contained inside an endosome, which merges with a lysosome.[3] The lysosome contains enzymes and acids that kill and digest the particle or organism. In general, phagocytes patrol the body searching for pathogens, but are also able to react to a group of highly specialized molecular signals produced by other cells, called cytokines. The phagocytic cells of the immune system include macrophages, neutrophils, and dendritic cells.

Phagocytosis of the hosts own cells is common as part of regular tissue development and maintenance. When host cells die, either internally induced by processes involving programmed cell death (also called apoptosis) or caused by cell injury due to a bacterial or viral infection, phagocytic cells are responsible for their removal from the affected site.[2] By helping to remove dead cells preceding growth and development of new healthy cells, phagocytosis is an important part of the healing process following tissue injury.

Macrophages, from the Greek, meaning "large eaters," are large phagocytic leukocytes, which are able to move outside of the vascular system by moving across the walls of capillary vessels and entering the areas between cells in pursuit of invading pathogens. In tissues, organ-specific macrophages are differentiated from phagocytic cells present in the blood called monocytes. Macrophages are the most efficient phagocytes, and can phagocytose substantial numbers of bacteria or other cells or microbes.[3] The binding of bacterial molecules to receptors on the surface of a macrophage triggers it to engulf and destroy the bacteria through the generation of a respiratory burst, causing the release of reactive oxygen species. Pathogens also stimulate the macrophage to produce chemokines, which summons other cells to the site of infection.[3]

Neutrophils, along with two other cell types; eosinophils and basophils (see below), are known as granulocytes due to the presence of granules in their cytoplasm, or as polymorphonuclear cells (PMNs) due to their distinctive lobed nuclei. Neutrophil granules contain a variety of toxic substances that kill or inhibit growth of bacteria and fungi. Similar to macrophages, neutrophils attack pathogens by activating a respiratory burst. The main products of the neutrophil respiratory burst are strong oxidizing agents including hydrogen peroxide, free oxygen radicals and hypochlorite. Neutrophils are the most abundant type of phagocyte, normally representing 50 to 60% of the total circulating leukocytes, and are usually the first cells to arrive at the site of an infection.[5] The bone marrow of a normal healthy adult produces more than 100 billion neutrophils per day, and more than 10 times that many per day during acute inflammation.[5]

Dendritic cells (DC) are phagocytic cells present in tissues that are in contact with the external environment, mainly the skin (where they are often called Langerhans cells), and the inner mucosal lining of the nose, lungs, stomach, and intestines.[2] They are named for their resemblance to neuronal dendrites, but dendritic cells are not connected to the nervous system. Dendritic cells are very important in the process of antigen presentation, and serve as a link between the innate and adaptive immune systems.

Basophils and eosinophils are cells related to the neutrophil (see above). When activated by a pathogen encounter, basophils releasing histamine are important in defense against parasites, and play a role in allergic reactions (such as asthma).[3] Upon activation, eosinophils secrete a range of highly toxic proteins and free radicals that are highly effective in killing bacteria and parasites, but are also responsible for tissue damage occurring during allergic reactions. Activation and toxin release by eosinophils is, therefore, tightly regulated to prevent any inappropriate tissue destruction.[5]

Natural killer cells, or NK cells, are a component of the innate immune system that does not directly attack invading microbes. Rather, NK cells destroy compromised host cells, such as tumor cells or virus-infected cells, recognizing such cells by a condition known as "missing self." This term describes cells with abnormally low levels of a cell-surface marker called MHC I (major histocompatibility complex) - a situation that can arise in viral infections of host cells.[7] They were named "natural killer" because of the initial notion that they do not require activation in order to kill cells that are "missing self." For many years, it was unclear how NK cell recognize tumor cells and infected cells. It is now known that the MHC makeup on the surface of those cells is altered and the NK cells become activated through recognition of "missing self". Normal body cells are not recognized and attacked by NK cells because they express intact self MHC antigens. Those MHC antigens are recognized by killer cell immunoglobulin receptors (KIR) that, in essence, put the brakes on NK cells. The NK-92 cell line does not express KIR and is developed for tumor therapy.[8][9][10][11]

Like other 'unconventional' T cell subsets bearing invariant T cell receptors (TCRs), such as CD1d-restricted Natural Killer T cells, T cells exhibit characteristics that place them at the border between innate and adaptive immunity. On one hand, T cells may be considered a component of adaptive immunity in that they rearrange TCR genes to produce junctional diversity and develop a memory phenotype. However, the various subsets may also be considered part of the innate immune system where a restricted TCR or NK receptors may be used as a pattern recognition receptor. For example, according to this paradigm, large numbers of V9/V2 T cells respond within hours to common molecules produced by microbes, and highly restricted intraepithelial V1 T cells will respond to stressed epithelial cells.

The coagulation system overlaps with the immune system. Some products of the coagulation system can contribute to the non-specific defenses by their ability to increase vascular permeability and act as chemotactic agents for phagocytic cells. In addition, some of the products of the coagulation system are directly antimicrobial. For example, beta-lysine, a protein produced by platelets during coagulation, can cause lysis of many Gram-positive bacteria by acting as a cationic detergent.[4] Many acute-phase proteins of inflammation are involved in the coagulation system.

Also increased levels of lactoferrin and transferrin inhibit bacterial growth by binding iron, an essential nutrient for bacteria.[4]

The innate immune response to infectious and sterile injury is modulated by neural circuits that control cytokine production period. The Inflammatory Reflex is a prototypical neural circuit that controls cytokine production in spleen.[12] Action potentials transmitted via the vagus nerve to spleen mediate the release of acetylcholine, the neurotransmitter that inhibits cytokine release by interacting with alpha7 nicotinic acetylcholine receptors (CHRNA7) expressed on cytokine-producing cells.[13] The motor arc of the inflammatory reflex is termed the cholinergic anti-inflammatory pathway.

The parts of the innate immune system have different specificity for different pathogens.

Cells of the innate immune system, in effect, prevent free growth of bacteria within the body; however, many pathogens have evolved mechanisms allowing them to evade the innate immune system.[15][16]

Evasion strategies that circumvent the innate immune system include intracellular replication, such as in Mycobacterium tuberculosis, or a protective capsule that prevents lysis by complement and by phagocytes, as in salmonella.[17]Bacteroides species are normally mutualistic bacteria, making up a substantial portion of the mammalian gastrointestinal flora.[18] Some species (B. fragilis, for example) are opportunistic pathogens, causing infections of the peritoneal cavity. These species evade the immune system through inhibition of phagocytosis by affecting the receptors that phagocytes use to engulf bacteria or by mimicking host cells so that the immune system does not recognize them as foreign. Staphylococcus aureus inhibits the ability of the phagocyte to respond to chemokine signals. Other organisms such as M. tuberculosis, Streptococcus pyogenes, and Bacillus anthracis utilize mechanisms that directly kill the phagocyte.

Bacteria and fungi may also form complex biofilms, providing protection from the cells and proteins of the immune system; recent studies indicate that such biofilms are present in many successful infections, including the chronic Pseudomonas aeruginosa and Burkholderia cenocepacia infections characteristic of cystic fibrosis.[19]

Type I interferons (IFN), secreted mainly by dendritic cells,[20] play the central role in antiviral host defense and creation of an effective antiviral state in a cell.[21] Viral components are recognized by different receptors: Toll-like receptors are located in the endosomal membrane and recognize double-stranded RNA (dsRNA), MDA5 and RIG-I receptors are located in the cytoplasm and recognize long dsRNA and phosphate-containing dsRNA respectively.[22] The viral recognition by MDA5 and RIG-I receptors in the cytoplasm induces a conformational change between the caspase-recruitment domain (CARD) and the CARD-containing adaptor MAVS. In parallel, the viral recognition by toll-like receptors in the endocytic compartments induces the activation of the adaptor protein TRIF. These two pathways converge in the recruitment and activation of the IKK/TBK-1 complex, inducing phosphorylation and homo- and hetero-dimerization of transcription factors IRF3 and IRF7. These molecules are translocated in the nucleus, where they induce IFN production with the presence of C-Jun (a particular transcription factor) and activating transcription factor 2. IFN then binds to the IFN receptors, inducing expression of hundreds of interferon-stimulated genes. This leads to production of proteins with antiviral properties, such as protein kinase R, which inhibits viral protein synthesis, or the 2,5-oligoadenylate synthetase family, which degrades viral RNA. These molecules establish an antiviral state in the cell.[21]

Some viruses are able to evade this immune system by producing molecules that interfere with the IFN production pathway. For example, the Influenza A virus produces NS1 protein, which can bring to single-stranded and double-stranded RNA, thus inhibiting type I IFN production. Influenza A virus also blocks protein kinase R activation and the establishment of the antiviral state.[23] The dengue virus also inhibits type I IFN production by blocking IRF-3 phosophorylation using NS2B3 protease complex.[24]

Bacteria (and perhaps other prokaryotic organisms), utilize a unique defense mechanism, called the restriction modification system to protect themselves from pathogens, such as bacteriophages. In this system, bacteria produce enzymes, called restriction endonucleases, that attack and destroy specific regions of the viral DNA of invading bacteriophages. Methylation of the host's own DNA marks it as "self" and prevents it from being attacked by endonucleases.[25] Restriction endonucleases and the restriction modification system exist exclusively in prokaryotes.

Invertebrates do not possess lymphocytes or an antibody-based humoral immune system, and it is likely that a multicomponent, adaptive immune system arose with the first vertebrates.[26] Nevertheless, invertebrates possess mechanisms that appear to be precursors of these aspects of vertebrate immunity. Pattern recognition receptors are proteins used by nearly all organisms to identify molecules associated with microbial pathogens. Toll-like receptors are a major class of pattern recognition receptor, that exists in all coelomates (animals with a body-cavity), including humans.[27] The complement system, as discussed above, is a biochemical cascade of the immune system that helps clear pathogens from an organism, and exists in most forms of life. Some invertebrates, including various insects, crabs, and worms utilize a modified form of the complement response known as the prophenoloxidase (proPO) system.[26]

Antimicrobial peptides are an evolutionarily conserved component of the innate immune response found among all classes of life and represent the main form of invertebrate systemic immunity. Several species of insect produce antimicrobial peptides known as defensins and cecropins.

In invertebrates, pattern recognition proteins (PRPs) trigger proteolytic cascades that degrade proteins and control many of the mechanisms of the innate immune system of invertebratesincluding hemolymph coagulation and melanization. Proteolytic cascades are important components of the invertebrate immune system because they are turned on more rapidly than other innate immune reactions because they do not rely on gene changes. Proteolytic cascades have been found to function the same in both vertebrate and invertebrates, even though different proteins are used throughout the cascades.[28]

In the hemolymph, which makes up the fluid in the circulatory system of arthropods, a gel-like fluid surrounds pathogen invaders, similar to the way blood does in other animals. There are various different proteins and mechanisms that are involved in invertebrate clotting. In crustaceans, transglutaminase from blood cells and mobile plasma proteins make up the clotting system, where the transglutaminase polymerizes 210 kDa subunits of a plasma-clotting protein. On the other hand, in the horseshoe crab species clotting system, components of proteolytic cascades are stored as inactive forms in granules of hemocytes, which are released when foreign molecules, like lipopolysaccharides enter.[28]

Members of every class of pathogen that infect humans also infect plants. Although the exact pathogenic species vary with the infected species, bacteria, fungi, viruses, nematodes, and insects can all cause plant disease. As with animals, plants attacked by insects or other pathogens use a set of complex metabolic responses that lead to the formation of defensive chemical compounds that fight infection or make the plant less attractive to insects and other herbivores.[29] (see: plant defense against herbivory).

Like invertebrates, plants neither generate antibody or T-cell responses nor possess mobile cells that detect and attack pathogens. In addition, in case of infection, parts of some plants are treated as disposable and replaceable, in ways that very few animals are able to do. Walling off or discarding a part of a plant helps stop spread of an infection.[29]

Most plant immune responses involve systemic chemical signals sent throughout a plant. Plants use pattern-recognition receptors to recognize conserved microbial signatures. This recognition triggers an immune response. The first plant receptors of conserved microbial signatures were identified in rice (XA21, 1995)[30][31] and in Arabidopsis (FLS2, 2000).[32] Plants also carry immune receptors that recognize highly variable pathogen effectors. These include the NBS-LRR class of proteins. When a part of a plant becomes infected with a microbial or viral pathogen, in case of an incompatible interaction triggered by specific elicitors, the plant produces a localized hypersensitive response (HR), in which cells at the site of infection undergo rapid programmed cell death to prevent the spread of the disease to other parts of the plant. HR has some similarities to animal pyroptosis, such as a requirement of caspase-1-like proteolytic activity of VPE, a cysteine protease that regulates cell disassembly during cell death.[33]

"Resistance" (R) proteins, encoded by R genes, are widely present in plants and detect pathogens. These proteins contain domains similar to the NOD Like Receptors and Toll-like receptors utilized in animal innate immunity. Systemic acquired resistance (SAR) is a type of defensive response that renders the entire plant resistant to a broad spectrum of infectious agents.[34] SAR involves the production of chemical messengers, such as salicylic acid or jasmonic acid. Some of these travel through the plant and signal other cells to produce defensive compounds to protect uninfected parts, e.g., leaves.[35] Salicylic acid itself, although indispensable for expression of SAR, is not the translocated signal responsible for the systemic response. Recent evidence indicates a role for jasmonates in transmission of the signal to distal portions of the plant. RNA silencing mechanisms are also important in the plant systemic response, as they can block virus replication.[36] The jasmonic acid response, is stimulated in leaves damaged by insects, and involves the production of methyl jasmonate.[29]

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Innate immune system - Wikipedia, the free encyclopedia

This page is about the immune system. It also tells you about the effects that cancer or treatments may have on the immune system. Some treatments can boost theimmune system tohelp fight cancer.There is information about

The immune system protects the body against illness and infection caused by bacteria, viruses, fungi or parasites. It is really a collection of reactions and responses that the body makes to damaged cells orinfection. So it is sometimes called the immune response.

The immune system is important to cancer patients in many ways because

Cancer can weaken the immune system by spreading into the bone marrow. The bone marrowmakesblood cells that help to fight infection. Weakening of the immune system happens most often in leukaemia or lymphoma. But it can happen with other cancers too. The cancer in the bone marrow stops the bone marrow making so many blood cells.

Chemotherapy, biological therapies andradiotherapy can temporarilyweaken immunity by causing a drop in the number of white blood cells made in the bone marrow. High doses of steroids can also weaken your immune system while you are taking them.

You can find information about the different types of cancer treatments.

Some cells of the immune system can recognise cancer cells as abnormal and kill them. Unfortunately, this may not beenough to get rid of a cancer altogether. But some new treatments aim to use the immune system to fight cancer.

There are two main parts of the immune system

This is also called innate immunity. These immune mechanisms are always ready and prepared to defend the body from infection. They can act immediately (or very quickly). This inbuilt protection comes from

There are several ways that these natural protection mechanisms can be damaged or overcome if you have cancer. For example

These white blood cells are very important for fighting infection.They can

Your normal neutrophil count is between 2,000 and 7,500 per cubic millimetre of blood. When you don't have enough neutrophils you are said to be neutropaenic.

Chemotherapy and some radiotherapy treatments can lower theneutrophil count. So, after chemotherapy, biological therapy and some types ofradiotherapy you may be more likely to get bacterial or fungal infections.

If you are having cancer treatment, it is important for you to know that

You are morelikely to become ill from bugs you carry around with you normally, not from catching someone else's. This means that you usually don't have to avoid your family, friends or children when you gohome after chemotherapy.

You can ask your cancer doctor or nurse what precautions you should take against infection.

When your blood counts are low, you may needto take antibiotics to help prevent severe infection.

This is immune protection thatthe body learns from being exposed to diseases. The body learns to recognise each different kind of bacteria, fungus orvirus it meets for the first time. The next time that particular bug tries to invade the body, the immune system is ready for it and able to fight it off more easily. This is why you usually only get some infectious diseases oncefor example, measles or chicken pox.

Vaccination works by using this type of immunity. A vaccine contains a small amount of protein from a disease. This is not harmful, but it allows the immune system to recognise the disease if it meets it again. The immune response can then stop you getting the disease. Some vaccines use tiny amounts of the live bacteria or virus. These are called live attenuated vaccines.

Attenuated means that the virus or bacteria has been changed so that it will stimulate the immune system to make antibodies but won't cause the infection. Other types of vaccine use killed bacteria or viruses, or parts of proteinsproduced by bacteria and viruses.

The white blood cells involved in the acquired immune response are called lymphocytes. There are two main types of lymphocytesB cells and T cells. B and T lymphocytes are made in the bone marrow, like the other blood cells.

Lymphocyteshave to fully mature before they can help in the immune response. B cells mature in the bone marrow. But the immature T cells travel through the bloodstream to the thymus gland where they become fully developed.

Once they are fully mature, the B and T cells travel to the spleen and lymph nodes ready to fight infection.

You can read about the thymus, spleen and lymph nodes on ourpage aboutthe lymphatic system and cancer.

B cells react against invading bacteria or viruses by making proteins called antibodies. The antibody made is different for each different type of germ (bug). The antibody locks onto the surface of the invading bacteria or virus. The invader is then marked with the antibody so that the body knows it is dangerous and it can be killed off. Antibodies can also detect and kill damaged cells.

The B cells are part of the memory of the immune system. The next time the same germtries to invade, the B cells that make the right antibody are ready for it. They are able to make their antibody very quickly.

Antibodies have two ends. One end sticks to proteins on the outside of white blood cells. The other end sticks to the germ or damaged cell and helps to kill it. The end of the antibody that sticks to the white blood cell is always the same. So it is called the constant end.

The end of the antibody that recognises germs and damaged cells varies depending on the cell it is designed to recognise. So it is called the variable end. Each B cell makes antibodies with a different variable end from other B cells.

Cancer cells are not normal cells. So some antibodies with variable ends recognise cancer cells and stick to them.

There are different kinds of T cells called

The helper T cells stimulate the B cells to make antibodies, and help killer cells develop.

Killer T cells kill the body's own cells that have been invaded by the viruses or bacteria. This prevents the germfrom reproducing in the cell and then infecting other cells.

Some cancertreatments use elements of the immune system to help treat cancer.

Immunotherapy is a type of biological therapy. Biological therapies use natural body substances or drugs made from natural body substances to treat cancer. Immunotherapies are treatments that use your immune system. They are helpful in cancer treatment because cancer cells are different from normal cells and so can be picked up by the immune system.

Many different chemicals produced as part of the immune response can now be made in the laboratory. These include interferon, interleukin 2 and monoclonal antibodies.

Interferon alpha and interleukin 2 act by boosting the immune response to help the body kill off cancer cells.

Scientists are also trying to develop vaccinations against cancer cells. It may be possible for the vaccine to train the immune system to see cancer cells as being invaders and kill them.

You can read more aboutbiological therapies.

Monoclonal antibodies are made in the laboratory. The scientists developing them make an antibody with a variable end that recognises cancer cells. Monoclonal means that all the antibodies are exactly the same type, with the same variable end.

The monoclonal antibodies recognise molecules on the outside of cancer cells. Different antibodies have to be made for different types of cancer, for example

The constant end of cancer treating monoclonal antibodies kills the cancer cells by marking them so that other immune system cells pick them out. The job of these other cells is to find antibody labelled cells and kill them.

Scientists can sometimes make the monoclonal antibody even better at killing cancer cells. They may attach a radioactive atom that delivers radiation directly to the cancer cells. Or they can attach a chemotherapy drug that is taken straight to the cancer cells by the monoclonal antibody.

Monoclonal antibodies are used for many types of cancer. You can find out moreabout monoclonal antibodies.

There is a lot of research going on into using immune system therapies to treat cancer. You can find information about monoclonal antibody trials on ourclinical trials database.

Many people with cancer believe that they should strengthen their immune systems to help beat the disease. There is a commonly held belief that reducing stress can help to strengthen our immune systems. This is the thinking behind some complementary therapies, such asusing relaxation techniques.

There is some scientific evidence that stress weakens our immunity. Two studies looking at whether stress affected cancer recurrence had conflicting results. While no one knows whether strengthening immunity can help to cure cancer, most doctors and nurses agree that reducing stress is a good thing to do.

While many life stresses cannot be avoided altogether, there are ways you can try to help yourself. Many complementary therapies such as meditation, massage and reflexology, can be very relaxing.

You can avoid getting run down and look after yourself by

You can find outaboutcomplementary therapies.

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The immune system and cancer | Cancer Research UK

By Dr. Mercola

Researchers have learned that circadian rhythmsthe 24-hour cycles known as your internal body clockare involved in everything from sleep to weight gain, mood disorders, and a variety of diseases.

Your body actually has many internal clocksin your brain, lungs, liver, heart and even your skeletal musclesand they all work to keep your body running smoothly by controlling temperature and the release of hormones.

It's well known that lack of sleep can increase your chances of getting sick. A new study shows just how direct that connection is.

The research found that the circadian clocks of mice control an essential immune system gene that helps their bodies sense and ward off bacteria and viruses. When levels of that particular gene, called toll-like receptor 9 (TLR9), were at their highest, the mice were better able to withstand infections.

Interestingly, when the researchers induced sepsis, the severity of the disease was dependent on the timing of the induction. Severity directly correlated with cyclical changes in TLR9.

According to the authors, this may help explain why septic patients are known to be at higher risk of dying between the hours of 2 am and 6 am.

Furthermore, they also discovered that when mice were vaccinated when TLR9 was peaking, they had an enhanced immune response to the vaccine. The researchers believe vaccine effectiveness could be altered depending on the time of day the vaccination is administered...

According to study author Erol Fikrig, professor of epidemiology at the Yale School of Medicinei:

"These findings not only unveil a novel, direct molecular link between circadian rhythms and the immune system, but also open a new paradigm in the biology of the overall immune response with important implications for the prevention and treatment of disease. Furthermore, patients in the ICU often have disturbed sleep patterns, due to noise, nocturnal light exposure and medications; it will be important to investigate how these factors influence TLR9 expression levels and immune responses."

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How Sleeping Can Affect Your Immune System

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If the same is true in humans, blocking the passage of these ... read more Scientists Find Molecular Switch That Creates Long-Term Immunity July 13, 2015 Researchers have identified a protein responsible for preserving the antibody-producing cells that lead to long-term immunity after infection or ... read more July 10, 2015 The microbiota is involved in many mechanisms, including digestion, vitamin synthesis and host defense. It is well established that a loss of bacterial symbionts promotes the development of ... read more Multiple Myeloma Hides in Bones Like a Wolf in Sheep's Clothing July 9, 2015 Multiple myeloma uses a trick akin to a wolf in sheeps clothing to grow in and spread to new bone sites. By overexpressing Runx2, a gene that normally is a master regulator of bone formation, the ... read more

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Immune System News -- ScienceDaily

Strong and vibrant Immune System Health is the key to overcoming chronic health problems. My name is Kerri Knox. I've been a Registered Nurse in intensive care units and emergency rooms for over a decade and now, as a Functional Medicine Practitioner, a specific type of natural health care practitioner that focuses on remedying chronic and traditionally 'incurable' health problems in my private practice every day, I've learned exactly what it takes for you to overcome your chronic health problems. You can see more about my Functional Medicine Practice here.

Having worked in Emergency Rooms and Intensive Care Units for over 10 years as a Registered Nurse, I was confused and frustrated at the inability of 'Western Medicine' to actually help people to get well. It was great for broken bones and appendicitis, but not so great for those with chronic 'incurable' diseases, and I saw the same people in the hospital and in clinics over and over again trying to simply maintain their poor health and poor quality of life. This frustration over our 'sick care system' inspired me to DO something about actually getting people WELL and improving their health- and I found that creating strong Immune System Health is the absolute key to getting well, overcoming illness and maintaining VIBRANT health!

In fact, 'Western Medicine', also called allopathic medicine or traditional medicine is so focused on managing disease that most people don't even REALIZE that they can overcome their health problems. But after working with thousands of people with health problems, in person and through my website and forums, I can assure you that you absolutely can overcome or at least SIGNIFICANTLY improve your 'incurable' chronic health issues- without drugs. Now that you know that you HAVE a choice, if you are willing to take the first steps to wellness, I'm committed to helping you feel better!

I'll share Scientifically Sound, Well Researched Secrets with you that few doctors know. Some of these secrets, like:

are secrets that have successfully helped tens of thousands of people to REALLY get well, improve their immune system health and Stay well.

To Your Good Health, Kerri Knox Registered Nurse and Functional Medicine Practitioner

Originally posted here:
Easy Immune System Health home page

To use the sharing features on this page, please enable JavaScript. Acquired Immunodeficiency Syndrome see HIV/AIDS Acute Lymphoblastic Leukemia see Acute Lymphocytic Leukemia Acute Lymphocytic Leukemia Addison Disease Adenoidectomy see Tonsils and Adenoids Adenoids see Tonsils and Adenoids Adenovirus Infections see Viral Infections Adrenal Insufficiency see Addison Disease Adult Immunization see Immunization AIDS see HIV/AIDS AIDS and Infections see HIV/AIDS and Infections AIDS and Pregnancy see HIV/AIDS and Pregnancy AIDS in Women see HIV/AIDS in Women AIDS Medicines see HIV/AIDS Medicines AIDS--Living With AIDS see Living with HIV/AIDS ALL see Acute Lymphocytic Leukemia Allergic Rhinitis see Allergy; Hay Fever Allergy Allergy, Food see Food Allergy Allergy, Latex see Latex Allergy Anaphylaxis see Allergy Anatomy Animal Bites Ankylosing Spondylitis Antimicrobial Resistance see Infectious Diseases Aplastic Anemia Asthma Asthma in Children Autoimmune Diseases Autoinflammatory Disorders see Autoimmune Diseases Bone Marrow Diseases Bone Marrow Transplantation Bronchial Asthma see Asthma Bullous Pemphigoid see Pemphigus Cat Bites see Animal Bites Chikungunya see Viral Infections Childhood Asthma see Asthma in Children Childhood Immunization Childhood Leukemia Chronic Granulomatous Disease see Immune System and Disorders Chronic Lymphocytic Leukemia Churg-Strauss Syndrome see Eosinophilic Disorders CLL see Chronic Lymphocytic Leukemia Communicable Diseases see Infectious Diseases Coxsackievirus Infections see Viral Infections Cryptosporidiosis Diabetes Type 1 Dog Bites see Animal Bites Dry Eye see Sjogren's Syndrome EBV Infections see Infectious Mononucleosis Enterovirus see Viral Infections Eosinophilia see Eosinophilic Disorders Eosinophilic Disorders Epstein-Barr Virus Infections see Infectious Mononucleosis Fanconi Anemia see Aplastic Anemia Food Allergy Giant Cell Arteritis Glandular Fever see Infectious Mononucleosis Hand, Foot, and Mouth Disease see Viral Infections Hay Fever HIV/AIDS HIV/AIDS and Infections HIV/AIDS and Pregnancy HIV/AIDS in Women HIV/AIDS Medicines HIV/AIDS--Living With see Living with HIV/AIDS Hives Hodgkin Disease Human Immunodeficiency Virus see HIV/AIDS Hypereosinophilic Syndrome see Eosinophilic Disorders Hypersensitivity see Allergy Immune System and Disorders Immunization Immunization, Childhood see Childhood Immunization Infections, Viral see Viral Infections Infectious Diseases Infectious Mononucleosis Insulin-Dependent Diabetes Mellitus see Diabetes Type 1 JRA see Juvenile Rheumatoid Arthritis Juvenile Diabetes see Diabetes Type 1 Juvenile Rheumatoid Arthritis Kawasaki Disease Latex Allergy Leukemia, Acute Lymphoblastic see Acute Lymphocytic Leukemia Leukemia, Acute Lymphocytic see Acute Lymphocytic Leukemia Leukemia, Childhood see Childhood Leukemia Leukemia, Chronic Lymphocytic see Chronic Lymphocytic Leukemia Living with HIV/AIDS Lupus Lymph Nodes see Lymphatic Diseases Lymphatic Diseases Lymphatic Obstruction see Lymphedema Lymphedema Lymphoma MDS see Myelodysplastic Syndromes Milk Allergy see Food Allergy Mono see Infectious Mononucleosis Mononucleosis see Infectious Mononucleosis Morphea see Scleroderma Mucocutaneous Lymph Node Syndrome see Kawasaki Disease Multiple Myeloma Myelodysplastic Syndromes Myeloproliferative Disorders see Bone Marrow Diseases Non-Hodgkin Lymphoma see Lymphoma Nut Allergy see Food Allergy Opportunistic Infections in AIDS see HIV/AIDS and Infections Peanut Allergy see Food Allergy Pemphigoid see Pemphigus Pemphigus Plasma-cell Myeloma see Multiple Myeloma Plasmacytoma see Multiple Myeloma Pneumocystis Infections Pollen Allergy see Hay Fever Pregnancy and AIDS see HIV/AIDS and Pregnancy PrEP (Pre-Exposure Prophylaxis) see HIV/AIDS Medicines Rheumatoid Arthritis Rheumatoid Spondylitis see Ankylosing Spondylitis Roseola see Viral Infections SCID see Immune System and Disorders Scleroderma Seasonal Allergies see Hay Fever Severe Combined Immunodeficiency see Immune System and Disorders Sjogren's Syndrome SLE see Lupus Snake Bites see Animal Bites Spleen Diseases Splenic Diseaess see Spleen Diseases Splenomegaly see Spleen Diseases Spondylitis, Ankylosing see Ankylosing Spondylitis Still's Disease see Juvenile Rheumatoid Arthritis Swollen Glands see Lymphatic Diseases Systemic Lupus Erythematosus see Lupus Systemic Sclerosis see Scleroderma Temporal Arteritis see Giant Cell Arteritis Thymus Cancer Tonsillectomy see Tonsils and Adenoids Tonsillitis see Tonsils and Adenoids Tonsils and Adenoids Type I Diabetes see Diabetes Type 1 Urticaria see Hives Vaccination see Childhood Immunization; Immunization Viral Infections Waldenstrom's Macroglobulinemia see Lymphoma

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Immune System: MedlinePlus - National Library of Medicine

Lack of sleep affects your immune system.

Mother knows best -- at least it appears that way when it comes to lack of sleep. It turns out that lack of sleep really may make us more prone to catching colds and the flu. And that includes the H1N1 virus.

It is an old wives tale that if you dont sleep well, you will get sick, and there is some experimental data that shows this is true, says Diwakar Balachandran, MD, director of the Sleep Center at the University of Texas M.D. Anderson Cancer Center in Houston.

When Nightmares Won't Go Away

Yael Levy recalls having chronic nightmares as far back as elementary school, when she was living in Israel. The grandchild of Holocaust survivors, she says her dreams were filled with images of suffering and death. In one recurrent nightmare, Levy was trapped in a concentration camp, facing death. In another, she was drowning in deep water. At their worst, the nightmares occurred on an almost weekly basis, leaving her jittery and desperately fatigued. "I would wake up so terrified that I was afraid...

Read the When Nightmares Won't Go Away article > >

Some 50 million to 70 million American adults suffer from sleep disorders or the inability to stay awake and alert, according to the CDC. Though its not always easy to do, getting adequate sleep can help keep our immune systems primed for attack.

Not getting enough sleep has been linked to a laundry list of mental and physical health problems, including those that stem from an impaired immune system. Our immune system is designed to protect us from colds, flu, and other ailments, but when it is not functioning properly, it fails to do its job. The consequences can include more sick days.

The relationship between lack of sleep and our immune systems is not quite as straightforward as mom made it out to be, however. The immune system is pretty complex. It is made up of several types of cells and proteins that are charged with keeping foreign invaders such as colds or flu at bay.

A lot of studies show our T-cells go down if we are sleep deprived, Balachandran says. And inflammatory cytokines go up. ... This could potentially lead to the greater risk of developing a cold or flu.

Read more:
Lack of Sleep and the Immune System - WebMD

By Dr. Mercola

Researchers have learned that circadian rhythmsthe 24-hour cycles known as your internal body clockare involved in everything from sleep to weight gain, mood disorders, and a variety of diseases.

Your body actually has many internal clocksin your brain, lungs, liver, heart and even your skeletal musclesand they all work to keep your body running smoothly by controlling temperature and the release of hormones.

It's well known that lack of sleep can increase your chances of getting sick. A new study shows just how direct that connection is.

The research found that the circadian clocks of mice control an essential immune system gene that helps their bodies sense and ward off bacteria and viruses. When levels of that particular gene, called toll-like receptor 9 (TLR9), were at their highest, the mice were better able to withstand infections.

Interestingly, when the researchers induced sepsis, the severity of the disease was dependent on the timing of the induction. Severity directly correlated with cyclical changes in TLR9.

According to the authors, this may help explain why septic patients are known to be at higher risk of dying between the hours of 2 am and 6 am.

Furthermore, they also discovered that when mice were vaccinated when TLR9 was peaking, they had an enhanced immune response to the vaccine. The researchers believe vaccine effectiveness could be altered depending on the time of day the vaccination is administered...

According to study author Erol Fikrig, professor of epidemiology at the Yale School of Medicinei:

"These findings not only unveil a novel, direct molecular link between circadian rhythms and the immune system, but also open a new paradigm in the biology of the overall immune response with important implications for the prevention and treatment of disease. Furthermore, patients in the ICU often have disturbed sleep patterns, due to noise, nocturnal light exposure and medications; it will be important to investigate how these factors influence TLR9 expression levels and immune responses."

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How Sleeping Can Affect Your Immune System - Mercola.com

14.00 Immune System Disorders

A. What disorders do we evaluate under the immune system disorders listings?

1. We evaluate immune system disorders that cause dysfunction in one or more components of your immune system.

a. The dysfunction may be due to problems in antibody production, impaired cell-mediated immunity, a combined type of antibody/cellular deficiency, impaired phagocytosis, or complement deficiency.

b. Immune system disorders may result in recurrent and unusual infections, or inflammation and dysfunction of the body's own tissues. Immune system disorders can cause a deficit in a single organ or body system that results in extreme (that is, very serious) loss of function. They can also cause lesser degrees of limitations in two or more organs or body systems, and when associated with symptoms or signs, such as severe fatigue, fever, malaise, diffuse musculoskeletal pain, or involuntary weight loss, can also result in extreme limitation.

c. We organize the discussions of immune system disorders in three categories: Autoimmune disorders; Immune deficiency disorders, excluding human immunodeficiency virus (HIV) infection; and HIV infection.

2. Autoimmune disorders (14.00D). Autoimmune disorders are caused by dysfunctional immune responses directed against the body's own tissues, resulting in chronic, multisystem impairments that differ in clinical manifestations, course, and outcome. They are sometimes referred to as rheumatic diseases, connective tissue disorders, or collagen vascular disorders. Some of the features of autoimmune disorders in adults differ from the features of the same disorders in children.

3. Immune deficiency disorders, excluding HIV infection (14.00E). Immune deficiency disorders are characterized by recurrent or unusual infections that respond poorly to treatment, and are often associated with complications affecting other parts of the body. Immune deficiency disorders are classified as either primary (congenital) or acquired. Individuals with immune deficiency disorders also have an increased risk of malignancies and of having autoimmune disorders.

4. Human immunodeficiency virus (HIV) infection (14.00F). HIV infection may be characterized by increased susceptibility to opportunistic infections, cancers, or other conditions, as described in 14.08.

B. What information do we need to show that you have an immune system disorder? Generally,

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14.00-Immune-Adult - Social Security Administration

The Immune System and Cancer - An Antibody (The Immunoglobulin)

Here are a few facts about the immune system and cancer. For most of your life, your immune system successfully fought cancerous cells, killing them as they developed. That's its job. In fact, the only job Natural Killer cells have is to kill cancer cells and viruses. For cancer to develop, your immune system must either be worn out, ineffective, unable to kill cancer cells as fast as they normally develop, or you must be exposed to a mass of cancer causing toxins, radiation or some such thing, that increase the rate of development of cancer cells to an abnormally high level that your immune system can't handle.

Either way, it is vital to strengthen the immune system in your battle against cancer . Especially if you are getting medical treatments that wipe out your immune system.

Many natural supplements support the immune system. This is why so many of them are touted as being able to help you beat cancer. If someone has an immune system that is almost able to handle the cancer, even a poor immune system supplement can be enough to improve the immune system to the extent that it beats cancer.

Of course, for folks with more seriously compromised immune systems, this supplement or group of supplements would not work well because they are in worse shape. This is why it can get so confusing in deciding what to use. When a supplement or procedure has been used for years, especially if it is popular, you'll hear how it has beat cancer.

But what you don't know is if it worked 2% of the time or 15% of the time. Given the number of people who die from cancer, the success rate of most of these supplements is fairly low. In this report we try to find and recommend the supplements that work the best, so that you have the greatest likelihood of success. It is easy to squander money and more importantly time, on products that won't get the job done.

The other concern is to make sure you do enough to wipe out the cancer. Cancer is not something to pussyfoot around with. While it is always hopeful and great to read about how someone took just one supplement and beat their cancer, and while that could happen to you, your odds of success are much higher if you take many different supplements in order to hit the cancer as hard as you can.

In order to determine which cancer fighting supplements are the most effective ones, we energetically test them for what we call their healing power. We have found this to be the most effective way of determining which supplements are likely to be the best to use. Our experience is that this works much better than taking a guess at what is good, and what isn't as good as it sounds.

When we started doing this we were surprised at how poorly the well known supplements and procedures tested. Many had been around for years and were popular, used by many patients and naturopaths, etc. But they actually weren't highly effective. Though they are good enough to help some people, and thus over time, produced plenty of testimonials, as you see in this report, we've been able to find many stronger products. Most of them new and thus unknown.

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Immune System - Cancer Fighting Strategies

What is the immune system?

We are surrounded by millions of bacteria, viruses and other microbes (germs) that have the potential to enter our bodies and cause harm. The immune system is the body's defence against pathogens (disease-causing microbes). The immune system is made up of non-specialised defences such as skin and the acidic juice produced by your stomach. But it also has some highly specialised defences which give you immunity against (resistance to) particular pathogens. These defences are special white blood cells called lymphocytes. Other types of white blood cells play an important part in defending your body against infection.

The lymphatic system is also part of the immune system. The lymphatic system is made up of a network of vessels (tubes) which carry fluid called lymph. It contains specialised lymph tissue and all of the structures dedicated to the production of lymphocytes.

The immune system is generally divided into two parts. The first part is the defences you are born with. These form what are known as the innate system.

The second part of your immune system, known as immunity, develops as you grow. Your immunity gives you protection against specific pathogens. Not only can this system recognise particular pathogens, it also has a memory of this. This means that if you encounter a certain pathogen twice, your immune system recognises it the second time around. This usually means your body responds quicker to fight off the infection.

The innate system is found in many different places around the body. First line of defence is your skin. Skin forms a waterproof barrier that prevents pathogens from entering the body. Your body cavities, such as the nose and mouth, are lined with mucous membranes. Mucous membranes produce sticky mucus which can trap bacteria and other pathogens. Other fluids produced by the body help to protect your internal layers from invasion by pathogens. Gastric juice produced by the stomach has high acidity which helps to kill off many of the bacteria in food. Saliva washes pathogens off your teeth and helps to reduce the amount of bacteria and other pathogens in your mouth.

If bacteria or other pathogens manage to get through these initial defences, they encounter a second line of defence. Most of these defences are present in your blood, either as specialised white blood cells or as chemicals released by your cells and tissues.

The second part of your immune system, the part that gives you immunity, involves the activation of lymphocytes. This will be described later on. Lymphocytes are found in your blood and also in specialised lymph tissue such as lymph nodes, the spleen and the thymus.

The first line of defence is your body's skin and mucous membranes, as mentioned above.

If pathogens manage to get through these barriers, they encounter special white blood cells present in your bloodstream. There are different types of white cells, called neutrophils (polymorphs), lymphocytes, eosinophils, monocytes, and basophils.

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The Immune System | Health | Patient.co.uk

The immune system, which is made up of special cells, proteins, tissues, and organs, defends people against germs and microorganisms every day. In most cases, the immune system does a great job of keeping people healthy and preventing infections. But sometimes problems with the immune system can lead to illness and infection.

The immune system is the body's defense against infectious organisms and other invaders. Through a series of steps called the immune response, the immune system attacks organisms and substances that invade body systems and cause disease.

The immune system is made up of a network of cells, tissues, and organs that work together to protect the body. The cells involved are white blood cells, or leukocytes, which come in two basic types that combine to seek out and destroy disease-causing organisms or substances.

Leukocytes are produced or stored in many locations in the body, including the thymus, spleen, and bone marrow. For this reason, they're called the lymphoid organs. There are also clumps of lymphoid tissue throughout the body, primarily as lymph nodes, that house the leukocytes.

The leukocytes circulate through the body between the organs and nodes via lymphatic vessels and blood vessels. In this way, the immune system works in a coordinated manner to monitor the body for germs or substances that might cause problems.

The two basic types of leukocytes are:

A number of different cells are considered phagocytes. The most common type is the neutrophil, which primarily fights bacteria. If doctors are worried about a bacterial infection, they might order a blood test to see if a patient has an increased number of neutrophils triggered by the infection. Other types of phagocytes have their own jobs to make sure that the body responds appropriately to a specific type of invader.

The two kinds of lymphocytes are B lymphocytes and T lymphocytes. Lymphocytes start out in the bone marrow and either stay there and mature into B cells, or they leave for the thymus gland, where they mature into T cells. B lymphocytes and T lymphocytes have separate functions: B lymphocytes are like the body's military intelligence system, seeking out their targets and sending defenses to lock onto them. T cells are like the soldiers, destroying the invaders that the intelligence system has identified.

Here's how it works:

Read the rest here:
Immune System - KidsHealth

Without it, we would all be forced to live in sterile environments, never touching each other, never feeling a spring breeze, never tasting rain. The immune system is that complex operation within our bodies that keeps us healthy and disease-free.

Few systems in nature are as complicated as the human immune system. It exists apart from, and works in concert with, every other system in the body. When it works, people stay healthy. When it malfunctions, terrible things happen.

The main component of the system is the lymphatic system. Small organs called lymph nodes help carry lymph fluid throughout the body. These nodes are located most prominently in the throat, armpit and groin. Lymph fluid contains lymphocytes and other white blood cells and circulates throughout the body.

The white blood cells are the main fighting soldiers in the body's immune system. They destroy foreign or diseased cells in an effort to clear them from the body. This is why a raised white blood cell count is often an indication of infection. The worse the infection, the more white blood cells the body sends out to fight it.

White and red blood cells are produced in the spongy tissue called bone marrow. This substance, rich in nutrients, is crucial for properly functioning immunity. Leukemia, a cancer of the bone marrow, causes greatly increased production of abnormal white blood cells and allows immature red blood cells to be released into the body. Other features, such as the lowly nose hair and mucus lining in the lungs, help trap bacteria before it gets into the bloodstream to cause an infection.

B cells and T cells are the main kinds of lymphocytes that attack foreign cells. B cells produce antibodies tailored to different cells at the command of the T cells, the regulators of the body's immune response. T cells also destroy diseased cells.

Many diseases that plague mankind are a result of insufficient immunity or inappropriate immune response. A cold, for instance, is caused by a virus. The body doesn't recognize some viruses as being harmful, so the T cell response is, "Pass, friend," and the sneezing begins.

Allergies are examples of inappropriate immune response. The body is hyper-vigilant, seeing that evil pollen as a dangerous invader instead of a harmless yellow powder. Other diseases, such as diabetes and AIDS, suppress the immune system, reducing the body's ability to fight infection.

Vaccines are vital in helping the body fend off certain diseases. The body is injected with a weakened or dead form of the virus or bacteria and produces the appropriate antibodies, giving complete protection against the full-strength form of the disease. This is the reason such disorders as diphtheria, mumps, tetanus and pertussis are so rarely seen today. Children have been vaccinated against them, and the immune system is on the alert. Vaccines have also been instrumental in eradicating plagues such as smallpox and polio.

Antibiotics help the body fight disease as well, but doctors are more cautious about prescribing the broad-spectrum variety, since certain bacteria are starting to show resistance to them. The next time you hug a loved one or smell a rose, thank your immune system.

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What Is the Immune System? (with pictures)

Elementary schools are breeding grounds for the common cold. Kids pass their germs around as often as they share their lunch. For children, catching a cold may not be a big deal. They might take it easy for a few days while their immune system kicks into action and fights off infection. But for their older teachers and grandparents, each cold can be more of a challenge. It may take a week or longer to get back to feeling 100 percent. Does that mean that the immune system gets weaker as we age? Thats what gerontologists are trying to figure out.

Our immune system is a complicated network of cells, tissues, and organs to keep us healthy and fight off disease and infection. The immune system is composed of two major parts: the innate immune system and the adaptive immune system. Both change as people get older. Studies to better understand these changes may lead to ways of supporting the aging immune system.

Innate immunity is our first line of defense. It is made up of barriers and certain cells that keep harmful germs from entering the body. These include our skin, the cough reflex, mucous membranes, and stomach acid. If germs are able to pass these physical barriers, they encounter a second line of innate defense, composed of specialized cells that alert the body of the impending danger. Research has shown that, with age, innate immune cells lose some of their ability to communicate with each other. This makes it difficult for the cells to react adequately to potentially harmful germs called pathogens, including viruses and bacteria.

Inflammation is an important part of our innate immune system. In a young person, bouts of inflammation are vital for fighting off disease. But as people age, they tend to have mild, chronic inflammation, which is associated with an increased risk for heart disease, arthritis, frailty, type 2 diabetes, physical disability, and dementia, among other problems. Researchers have yet to determine whether inflammation leads to disease, disease leads to inflammation, or if both scenarios are true. Interestingly, centenarians and other people who have grown old in relatively good health generally have less inflammation and a more efficient recovery from infection and inflammation when compared to people who are unhealthy or have average health. Understanding the underlying causes of chronic inflammation in older individualsand why some older people do not have this problemmay help gerontologists find ways to temper its associated diseases.

The adaptive immune system is more complex than the innate immune system and includes the thymus, spleen, tonsils, bone marrow, circulatory system, and lymphatic system. These different parts of the body work together to produce, store, and transport specific types of cells and substances to combat health threats. T cells, a type of white blood cell (called lymphocytes) that fights invading bacteria, viruses, and other foreign cells, are of particular interest to gerontologists.

T cells attack infected or damaged cells directly or produce powerful chemicals that mobilize an army of other immune system substances and cells. Before a T cell gets programmed to recognize a specific harmful germ, it is in a nave state. After a T cell is assigned to fight off a particular infection, it becomes a memory cell. Because these cells remember how to resist a specific germ, they help you fight a second round of infection faster and more effectively. Memory T cells remain in your system for many decades.

A healthy young persons body is like a T cell producing engine, able to fight off infections and building a lifetime storehouse of memory T cells. With age, however, people produce fewer nave T cells, which makes them less able to combat new health threats. This also makes older people less responsive to vaccines, because vaccines generally require nave T cells to produce a protective immune response. One exception is the shingles vaccine. Since shingles is the reactivation of the chickenpox virus, this particular vaccine relies on existing memory T cells and has been particularly effective in older people. Researchers are investigating ways to develop other vaccines that are adjusted for the changes that happen in an older persons immune system.

Negative, age-related changes in our innate and adaptive immune systems are known collectively as immunosenescence. A lifetime of stress on our bodies is thought to contribute to immunosenescence. Radiation, chemical exposure, and exposure to certain diseases can also speed up the deterioration of the immune system. Studying the intricacies of the immune system helps researchers better understand immunosenescence and determine which areas of the immune system are most vulnerable to aging. Ongoing research may shed light on whether or not there is any way to reverse the decline and boost immune protection in older individuals.

Adapted from http://www.niaid.nih.gov

Our ability to survive the germs around us is based on a tightly controlled immune system. Too little of an immune response makes us susceptible to infection, including life-threatening pneumonia. Conversely, an overactive immune response is at the root of autoimmune diseases common among older people and may contribute to age-related chronic diseases like Alzheimers disease, osteoarthritis, diabetes, and heart disease. So, should scientists try to change the immune response in older people, or is immunosenescence somehow beneficial within the context of the aging body?

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Immune System: Can Your Immune System ... - Biology of Aging

The adaptive immune system, also known as the acquired immune or, more rarely, as the specific immune system, is a subsystem of the overall immune system that is composed of highly specialized, systemic cells and processes that eliminate or prevent pathogen growth. The adaptive immune system is one of the two main immunity strategies found in vertebrates (the other being the innate immune system). Adaptive immunity creates immunological memory after an initial response to a specific pathogen, leads to an enhanced response to subsequent encounters with that pathogen. This process of acquired immunity is the basis of vaccination. Like the innate system, the adaptive system includes both humoral immunity components and cell-mediated immunity components.

Unlike the innate immune system, the adaptive immune system is highly specific to a specific pathogen. Adaptive immunity can also provide long-lasting protection: for example; someone who recovers from measles is now protected against measles for their lifetime but in other cases it does not provide lifetime protection: for example; chickenpox. The adaptive system response destroys invading pathogens and any toxic molecules they produce. Sometimes the adaptive system is unable to distinguish foreign molecules, the effects of this may be hayfever, asthma or any other allergies. Antigens are any substances that elicit the adaptive immune response. The cells that carry out the adaptive immune response are white blood cells known as lymphocytes. There are two main broad classes- antibody responses and cell mediated immune response which are also carried by two different lymphocytes (B cells and T cells). In antibody responses, B cells are activated to secrete antibodies, which are proteins also known as immunoglobulins. Antibodies travel through the bloodstream and bind to the foreign antigen causing it to inactivate, which does not allow the antigen to bind to the host.[1]

In acquired immunity, pathogen-specific receptors are "acquired" during the lifetime of the organism (whereas in innate immunity pathogen-specific receptors are already encoded in the germline). The acquired response is said to be "adaptive" because it prepares the body's immune system for future challenges (though it can actually also be maladaptive when it results in autoimmunity).[n 1]

The system is highly adaptable because of somatic hypermutation (a process of accelerated somatic mutations), and V(D)J recombination (an irreversible genetic recombination of antigen receptor gene segments). This mechanism allows a small number of genes to generate a vast number of different antigen receptors, which are then uniquely expressed on each individual lymphocyte. Because the gene rearrangement leads to an irreversible change in the DNA of each cell, all of the progeny (offspring) of that cell will then inherit genes encoding the same receptor specificity, including the memory B cells and memory T cells that are the keys to long-lived specific immunity.

A theoretical framework explaining the workings of the acquired immune system is provided by immune network theory. This theory, which builds on established concepts of clonal selection, is being applied in the search for an HIV vaccine.

Acquired immunity is triggered in vertebrates when a pathogen evades the innate immune system and (1) generates a threshold level of antigen and (2) generates "stranger" or "danger" signals activating dendritic cells.[2]

The major functions of the acquired immune system include:

The cells of the acquired immune system are T and B lymphocytes; lymphocytes are a subset of leukocyte. B cells and T cells are the major types of lymphocytes. The human body has about 2 trillion lymphocytes, constituting 2040% of white blood cells (WBCs); their total mass is about the same as the brain or liver.[3] The peripheral blood contains 2% of circulating lymphocytes; the rest move within the tissues and lymphatic system.[3]

B cells and T cells are derived from the same multipotent hematopoietic stem cells, and are morphologically indistinguishable from one another until after they are activated.[4] B cells play a large role in the humoral immune response, whereas T cells are intimately involved in cell-mediated immune responses. In all vertebrates except Agnatha, B cells and T cells are produced by stem cells in the bone marrow.[4] T progenitors migrate from the bone marrow to the thymus where they are called thymocytes and where they develop into T cells. In humans, approximately 12% of the lymphocyte pool recirculates each hour to optimize the opportunities for antigen-specific lymphocytes to find their specific antigen within the secondary lymphoid tissues.[5]

In an adult animal, the peripheral lymphoid organs contain a mixture of B and T cells in at least three stages of differentiation:

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Adaptive immune system - Wikipedia, the free encyclopedia

[Continued from above] . . . andother organs that transport a fluid called lymph from the tissues as it returns to the bloodstream. The lymphatic tissue of these organs filters and cleans the lymph of any debris, abnormal cells, or pathogens. The lymphatic system also transports fatty acids from the intestines to the circulatory system.

Red Bone Marrow and Leukocytes Red bone marrow is a highly vascular tissue found in the spaces between trabeculae of spongy bone. It is mostly found in the ends of long bones and in the flat bones of the body. Red bone marrow is a hematopoietic tissue containing many stem cells that produce blood cells. All of the leukocytes, or white blood cells, of the immune system are produced by red bone marrow. Leukocytes can be further broken down into 2 groups based upon the type of stem cells that produces them: myeloid stem cells and lymphoid stem cells.

Myeloid stem cells produce monocytes and the granular leukocyteseosinophils, basophils, and neutrophils.

Lymphoid stem cells produce T lymphocytes and B lymphocytes.

Lymph Capillaries As blood passes through the tissues of the body, it enters thin-walled capillaries to facilitate diffusion of nutrients, gases, and wastes. Blood plasma also diffuses through the thin capillary walls and penetrates into the spaces between the cells of the tissues. Some of this plasma diffuses back into the blood of the capillaries, but a considerable portion becomes embedded in the tissues as interstitial fluid. To prevent the accumulation of excess fluids, small dead-end vessels called lymphatic capillaries extend into the tissues to absorb fluids and return them to circulation.

Lymph The interstitial fluid picked up by lymphatic capillaries is known as lymph. Lymph very closely resembles the plasma found in the veins: it is a mixture of about 90% water and 10% solutes such as proteins, cellular waste products, dissolved gases, and hormones. Lymph may also contain bacterial cells that are picked up from diseased tissues and the white blood cells that fight these pathogens. In late-stage cancer patients, lymph often contains cancerous cells that have metastasized from tumors and may form new tumors within the lymphatic system. A special type of lymph, known as chyle, is produced in the digestive system as lymph absorbs triglycerides from the intestinal villi. Due to the presence of triglycerides, chyle has a milky white coloration to it.

Lymphatic Vessels Lymphatic capillaries merge together into larger lymphatic vessels to carry lymph through the body. The structure of lymphatic vessels closely resembles that of veins: they both have thin walls and many check valves due to their shared function of carrying fluids under low pressure. Lymph is transported through lymphatic vessels by the skeletal muscle pumpcontractions of skeletal muscles constrict the vessels to push the fluid forward. Check valves prevent the fluid from flowing back toward the lymphatic capillaries.

Lymph Nodes Lymph nodes are small, kidney-shaped organs of the lymphatic system. There are several hundred lymph nodes found mostly throughout the thorax and abdomen of the body with the highest concentrations in the axillary (armpit) and inguinal (groin) regions. The outside of each lymph node is made of a dense fibrous connective tissue capsule. Inside the capsule, the lymph node is filled with reticular tissue containing many lymphocytes and macrophages. The lymph nodes function as filters of lymph that enters from several afferent lymph vessels. The reticular fibers of the lymph node act as a net to catch any debris or cells that are present in the lymph. Macrophages and lymphocytes attack and kill any microbes caught in the reticular fibers. Efferent lymph vessels then carry the filtered lymph out of the lymph node and towards the lymphatic ducts.

Lymphatic Ducts All of the lymphatic vessels of the body carry lymph toward the 2 lymphatic ducts: the thoracic duct and the right lymphatic ducts. These ducts serve to return lymph back to the venous blood supply so that it can be circulated as plasma.

Lymphatic Nodules Outside of the system of lymphatic vessels and lymph nodes, there are masses of non-encapsulated lymphatic tissue known as lymphatic nodules. The lymphatic nodules are associated with the mucous membranes of the body, where they work to protect the body from pathogens entering the body through open body cavities.

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Immune and Lymphatic Systems Anatomy Pictures and ...