A helper T cell response to a protein antigen requires the participation of antigen-presenting cells that express which of the following types of molecules?
A)Class II MHC and costimulators
B)Class I MHC and CD4
C)Class II MHC and CD8
D)CD4 and costimulators
E)Class II MHC and CD4

Question

Quizplus · Accepted Answer

Helper T cells are almost always CD4+.The activation of naive CD4+ T cells requires T cell receptor recognition of class II MHC-peptide complexes and the binding of costimulators,both on the antigen-presenting cell (APC)surface.CD4+ helper T cells bind to class II MHC molecules on the APC,not to class I MHC molecules.CD4 or CD8 expression on the APC surface is of no known relevance to T cell activation.

A Helper T Cell Response to a Protein Antigen Requires