The human immune system is truly a wonder. It plays a critical role in our body’s defense to invading disease. Like a home security system, it is on alert 24/7/365. Through multiple mechanisms, it guards all our tissues, protects us from microbial foreign invaders, and removes cancer cells to keep us disease-free. For example, B cells are responsible for the production of antibody proteins. These proteins recognize and target specific invaders, which are then removed by other cells. Another type of immune cell, called T cells, can directly interact with and kill foreign invaders and help orchestrate other elements of the “host response” that protects us.
New therapies for cancer have focused on activating and enhancing the immune system, specifically T cells. One approach is to engineer T cells to recognize and kill cancer cells through a protein called a chimeric antigen receptor (CAR). In this therapy, scientists take T cells from a patient’s blood and manipulate them in the laboratory so that they attack the patient’s cancer cells. The scientists program the T cells to attack cancer cells by adding a gene that produces this CAR protein. The CAR protein helps the T cells recognize and kill cancer cells. Scientists grow large numbers of these cells in the laboratory and infuse them into the patient, providing millions of T cells dedicated to removing the cancer cells. These CAR T cells will stay in the body and continue to fight the cancer. CAR T cell therapy is the ultimate in personalized cancer therapy designed precisely for the person’s individual cancer.