Calcineurin inhibitors include which drug?

Calcineurin inhibitors include which drug?

• A. Mycophenolate mofetil
• B. Sirolimus
• C. Azathioprine
• D. Cyclosporine

Answer: (D)

Calcineurin inhibitors block a calcium-activated phosphatase needed for T cell activation. They prevent NFAT from driving IL-2 transcription, so T cells don’t proliferate effectively. Cyclosporine achieves this by binding cyclophilin to form a complex that inhibits calcineurin, making it the drug in this list that fits the calcineurin-inhibitor category. The other medications work by different pathways—mycophenolate mofetil blocks purine synthesis; sirolimus inhibits mTOR signaling; azathioprine is a purine analog affecting DNA synthesis. Thus cyclosporine is the drug that fits the calcineurin-inhibitor class.

Calcineurin inhibitors block a calcium-activated phosphatase needed for T cell activation. They prevent NFAT from driving IL-2 transcription, so T cells don’t proliferate effectively. Cyclosporine achieves this by binding cyclophilin to form a complex that inhibits calcineurin, making it the drug in this list that fits the calcineurin-inhibitor category. The other medications work by different pathways—mycophenolate mofetil blocks purine synthesis; sirolimus inhibits mTOR signaling; azathioprine is a purine analog affecting DNA synthesis. Thus cyclosporine is the drug that fits the calcineurin-inhibitor class.