When a presented antigen fragment interacts with the T cell receptor of a helper T cell,the co-receptor that must also participate to finalize recognition is

Question

Quizplus · Accepted Answer

CD4 is the co-receptor that interacts with the MHC II molecule on the surface of the antigen-presenting cell in order to stabilize the T cell receptor-antigen fragment complex and ultimately activate the helper T cell. CD8 is involved in the recognition of antigens presented on MHC I molecules by cytotoxic T cells, and MHC I is not involved in recognition by helper T cells.

When a Presented Antigen Fragment Interacts with the T Cell