Immunosuppression

Using drugs to weaken the immune system so that it does not reject a transplanted organ.

The turning point that made organ transplantation routine was cyclosporin, reported by Jean-François Borel and colleagues in 1976^[1]. By selectively suppressing T cells, which direct the immune response, it allowed transplanted organs to last far longer once it entered use in the 1980s.

The more the immune system is suppressed, the better rejection is prevented, but the higher the risk of infection and cancer. Striking that balance strongly affects how long a graft survives, in human and animal transplants alike.