Immunotherapy
Each cell, no matter if healthy, diseased or exogenous (foreign), possesses specific molecular structures (antigens) on its surface. The cells can be distinguished by expression of these antigens. Antibodies produced by immune cells are able to identify and destroy exogenous antigens. Cancer cells, though, possess a good system that disguises these antigens. Thus, the human immune system often does not recognize them as threatening. To support the body’s defenses fighting against cancer cells, specific antibodies are artificially produced.
The latest studies focus on the identification of substances on cancer cells (tumor antigens) in order to produce targeted monoclonal antibodies made in the laboratory.
Passive Immunotherapy – Monoclonal Antibodies
In passive immunotherapy, synthetically produced monoclonal antibodies directed against a specific antigen are directly given into the body, thus support comes “from the outside“.
The use of monoclonal antibodies has been successful in various types of cancer. So far, in colorectal cancer, chemotherapy is more effective. Therefore, more research needs to be done to improve the efficiency of monoclonal antibodies.
Active Immunotherapy
In active immunotherapy, the body’s defense system is trained by vaccines (so-called tumor vaccines) in order to better recognize and fight cancer cells. This kind of vaccination is not preventive, but only a treatment option for the disease itself. An aggravating factor is that the cancer cells have various strategies to avoid their discovery and destruction. Cancer cells may have numerous tumor antigens, even individually different antigens, or they mingle among healthy cells, pretending to be of no threat. More studies still need to be done in this area in order to achieve a better understanding of the mechanisms involved in this process.