Transplantation

Transplantation is the surgical transfer of cells, tissues, or organs from a donor to a recipient to replace damaged function. It includes organ transplants (kidney, liver, heart, lung, pancreas, intestine) and tissue transplants (cornea, skin, bone, tendons, heart valves). Donor sources are typically deceased for organs and living for some tissues or organs, such as kidney or liver segments.

Donor-recipient matching uses ABO blood type, human leukocyte antigen (HLA) compatibility, size, and other factors. A crossmatch detects preformed antibodies that could trigger rejection. Allocation systems aim to balance medical urgency, likelihood of success, and waiting time.

Post-transplant care relies on lifelong immunosuppression to prevent rejection, with regimens that may include calcineurin inhibitors, antiproliferatives, steroids, and newer agents. Rejection can be hyperacute, acute, or chronic. Immunosuppression raises infection and cancer risks and requires regular monitoring.

Transplantation emerged in the mid-20th century; the modern era improved dramatically with immunosuppressive drugs in the 1980s. Ethical issues include donor consent, donor risk, and fair organ allocation, which is managed by national or regional systems to optimize equity and outcomes.

Outcomes vary by organ and patient factors. Kidney transplants commonly offer improved survival and quality of life relative to dialysis, while heart and liver transplants can restore function in end-stage disease. Research continues to expand donor pools, refine matching, and minimize immunosuppression side effects.