Question

After activation of a T cell, what happens to CD152 (CTLA-4)?

a) It remains sequestered in the Golgi.
b) It binds to pMHC.
c) It inhibits IL-2 production.
d) It activates CD28.
e) It moves to the cell surface and competes with CD28 for binding to CD80/CD86 on antigen-presenting cells.

Answer 1

After activation of a T cell, CD152 (CTLA-4) moves to the cell surface and inhibits IL-2 production by competing with CD28 for binding to CD80/CD86 on antigen-presenting cells.

Step-by-step explanation:

After activation of a T cell, CD152 (CTLA-4) moves to the cell surface and competes with CD28 for binding to CD80/CD86 on antigen-presenting cells. This interaction between CD152 and CD80/CD86 inhibits IL-2 production, which is a cytokine necessary for T cell proliferation and survival. This helps to downregulate the immune response and maintain immune homeostasis.