Cyclosporin a and Rapamycin Are Each Used as T Cell

Multiple Choice

Cyclosporin A and rapamycin are each used as T cell immunosuppressants. They share the property of binding to immunophilin molecules in T cells as the initial step in their mechanisms of action. However, in the case of cyclosporin A, the drug:immunophilin complex binds to and inhibits the protein phosphatase calcineurin, whereas the rapamycin:immunophilin complex binds to and inhibitors mTOR. As a consequence,

A) Cyclosporin A, but not rapamycin, blocks cytokine production by T cells.
B) Both cyclosporin A and rapamycin block cytokine production by T cells.
C) Rapamycin, but not cyclosporin A, blocks T cell proliferation.
D) Neither rapamycin nor cyclosporin A block T cell proliferation.
E) Both cyclosporin A and rapamycin inhibit co-stimulatory signaling through CD28 on T cells.