Potent immunosuppressant (same as FK-506 (Prod. No. AG-CN2-0047) and rapamycin (Prod. No. AG-CN2-0025)). Forms a complex with cyclophilin. Inhibits the activity of the calcium/calmodulin-dependent protein phosphatase 2B (PP2B; calcineurin). Prevents the dephosphorylation of nuclear factor of activated T cells (NFAT) transcription factor, leading to disruption of T cell activation. Suppresses proliferation of cytotoxic T cells and inhibits the production of T cell-derived mediators such as interleukin-2 (IL-2). Prevents rejection of transplanted organs. Anti-inflammatory compound in the treatment of several inflammatory skin diseases (e.g. atopic dermatitis) and with potential anti-rheumatic activity (rheumatoid arthritis). Antibacterial. Antifungal. Antiparasitic. Apoptosis inhibitor. Inhibits the mitochondrial permeability transition pore (MPTP) from opening, thus inhibiting cytochrome c release. NF-kappaB suppressor by induction of unfolded protein response (UPR). Anti-cancer compound. Apoptosis and autophagy inducer. Inhibits nitric oxide synthesis induced by interleukin-1alpha, lipopolysaccharides and TNF-alpha. Potently induces highly cardiogenic progenitors from embryonic stem (ES) cells.