Cyclosporin A (CsA)

Cyclosporin A is a non-polar cyclic oligopeptide metabolite. It possesses potent immunosuppressive properties, affecting primarly T-lymphocytes. Cyclosporin A is the primary tool used to prevent rejection following solid organ and/or bone marrow transplantation. Cyclosporin A inhibits phosphatase activity of calcineurin. This small molecule also inhibits formation and opening of the mitochondrial permeability transition pore (MPTP).