Cyclosporin A in organ transplantation.

Cyclosporin A is a novel, powerful immunosuppressive agent. It is a cyclic polypeptide and is one of several metabolites of a number of soil fungi. Its main effect is directed against the helper T lymphocyte. Thus, cyclosporin A represents the first of a new generation of immunosuppressive agents that are capable of selective rather than broad spectrum activity. The immunosuppressive properties of cyclosporin A have been applied successfully to prevent the rejection of transplanted organs both in animals and humans. Clinically, it has been used in the management of transplanted kidneys, hearts, lungs, livers and, to some degree, pancreases and bone marrow. It is also finding some application in the control of various autoimmune conditions. The clinical use of cyclosporin A is still in an early phase and several aspects have not been defined optimally. The most common and troublesome side-effect is nephrotoxicity. Other adverse effects include hirsutism, gum hypertrophy and mild psychiatric disturbances as well as involvement of the gastrointestinal tract, liver and central nervous system.