About Cyclosporin A A cyclic nonribosomal peptide(11 amino acids) immunosuppressant drug, Organ transplant rejection prevention. Mechanism of Action of Cyclosporin A Cyclosporine binds to the cytosolic protein cyclophilin (immunophilin) of immunocompetent lymphocytes, especially T-lymphocytes. This complex inhibits calcineurin, which is responsible for activating the transcription of interleukin 2. It also inhibits lymphokine production and interleukin release and therefore leads to reduced function of effecter T-cells. Drug prevents mitochondrial PT pore from opening and inhibits cytochrome C release and also apoptosis induced by it. Indications for Cyclosporin A 1. Organ transplant rejection 2. Rheumatoid arthritis 3. Crohn`s syndrome 4. Nephrotic syndrome 5. Psoriasis 6. Ulcerative colitis 7. Uveitis 8. Neuroprotection in traumatic brain injury 9. Aplastic anemia 10. Myasthenia gravis 11. Dermatomyositis