For years, immunotherapy has been used to alleviate the effect of tumors on the human body. Under immunotherapy, the immune cells within the body are stimulated to rapidly attack the tumor, and ultimately cause it to die. Melanoma, which is a severe form of skin tumor, is treated with the help of immunotherapy but the success rate is extremely low and most patients succumb to the disease. In order to attain better treatment standards, researchers are trying to find new ways of administering immunotherapy so that it destroys melanoma and other types of cancers. CD8 T cells are a type of immune cells that have the ability to selectively recognize and kill melanoma cells. Immunotherapy empowers the actions of CD8 T cells but other immune cells present in the tumor can inhibit the actions of CD8 T cells.
Premise of Research
CD8 T cells need to be channeled towards an anti-melanoma action or else they can result in expansion of the tumor. In their activated state, CD8 T cells can generate a protein called CSF1 in melanoma, which in turn attracts macrophages. Macrophages can weaken the efficacy of immunotherapy and may lead to the growth of the tumor. On the positive side, CD8 T cells may even get activated by antigens of the tumor and successively advent an attack on the tumor. Since the macrophages inhibit the anti-tumor action of the CD8 T cells, the scientists used a drug to eliminate the macrophages from the experimental melanoma models.
Concerns and Challenges
Despite the positive results of the research, the lack of biomarkers for immunotherapy raises doubts about the effectiveness of such a mechanism on all the patients. It would be interesting to see the course of action that the research takes over the coming years.