Immunotherapy for Mesothelioma

Active Immunotherapy

Cancer vaccines are a form of immunotherapy currently being studied and developed. Vaccines expose a person to a weakened version of a bacteria or virus; the exposure causes the immune system to increase production of plasma cells which make specific antibodies that target them. The immune system also increases production of T cells that recognize the infectious agent. These activated immune cells remember the exposure, so the next time the agent enters the body, the immune system is prepared to respond.

Researchers hope to replicate this response in regards to cancer cells. Cancer vaccines are designed to treat existing cancers or to prevent the development of cancer. There are two types of vaccines therapeutic, which are injected after diagnosis and preventative which are given to healthy individuals as a means of prevention.

Therapeutic vaccines may halt the growth of existing tumors, prevent cancer from reappearing or destroy cancer cells not eliminated by prior treatments. Administering the vaccine while a tumor is still early in it’s development may be able to eradicate it.

Preventative vaccines are given to healthy individuals before cancer develops as a means of preventing certain types of cancer by targeting viruses that can cause them.

Passive Immunotherapy

Passive immunotherapy works by taking cancer cells from the patient and then creating super cells that produce massive amounts of antibodies to that cancer. These cells are then re-introduced to the body to hopefully aid the patient.

An Antibody is a Y shaped protein used by your immune system to help fight infections by identifying and helping it to remove bacteria and viruses. At the top of the Y are 2 bonding areas with specific patterns that bond only to 1 type of antigen, which are the chemical patterns on receptor areas of infected cells, bacteria, or viruses.

Thus when your body determines the specific antigen, it makes a number of antibodies to combat it. Since each antibody has a specific target that only it will recognize, producing antibodies that target specific kinds of cancer can be incredibly useful. One problem however is that some cancer cells can mask their antigens or the new cells block other cells from responding.

Non-Specific Immunotherapy

In the early 1970s, it was found that the administration of weakened forms of a mycobacterial strain called Bacille Calmette-Guerin (BCG) had anticancer effects. Since then BCG has become a viable treatment for early stages of some cancers. More on targeted therapies.

Another useful cancer fighter are cytokines. These are produced as a way of cells communicating between one another which includes helping coordinate immune system responses. They can benefit patients are by stimulating cells to increase production of “killer” T-cells or acting as antigens to stimulate antibody production.