[Immunosuppressive treatment after organ transplantation].

The success of organ transplantation depends mostly on immunosuppressive treatments which depress the host vs allograft immune response. The drugs mostly used in the past, Azathioprine and Corticosteroids, act in a non specific way. Heterologous antilymphocyte sera are progressively replaced by monoclonal antibodies specific of lymphocyte subpopulations, such as OKT3 which is a highly potent immunosuppressive agent. Cyclosporin, a new original immunosuppressive agent which acts specifically on T lymphocytes, has considerably improved organ graft survival rates especially for heart and liver. Moreover, it allows reduction of the doses or corticosteroids given after transplantation an thus limits their side-effects, especially on statural growth. However, cyclosporin nephrotoxicity represents the major problem, at least in the long-term.