Transplant immunology is the study of how the immune system responds to transplanted organs or tissues. When a person receives a transplant, their body may recognize the new tissue as foreign and attempt to reject it. This response is primarily mediated by T cells, which are a type of white blood cell that plays a crucial role in the immune response. To prevent rejection, doctors often prescribe immunosuppressive drugs that help dampen the immune response. These medications allow the body to accept the transplant while reducing the risk of rejection. Understanding transplant immunology is essential for improving transplant success rates and patient outcomes.