StemCell Therapy

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.

The rest is here:
The immune system and cancer | Cancer Research UK

This entry was posted on August 19, 2015 at 4:42 pm and is filed under Immune System. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed. |