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, Cyclosporin A, but not rapamycin, blocks cytokine production by T cells. Both cyclosporin A and rapamycin block cytokine production by T cells. Rapamycin, but not cyclosporin A, blocks T cell proliferation.

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, Cyclosporin A, but not rapamycin, blocks cytokine production by T cells. Both cyclosporin A and rapamycin block cytokine production by T cells. Rapamycin, but not cyclosporin A, blocks T cell proliferation.

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter17: Genes And The Immune System

Section: Chapter Questions

Problem 11QP: It is often helpful to draw a complicated pathway in the form of a flow chart to visualize the...

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