The purpose of the invariant chain (Ii,CD74)is to block the peptide-binding site of:

Question

Quizplus · Accepted Answer

The invariant chain (Ii,CD74) blocks the peptide-binding site of class II molecules, which are involved in presenting antigenic peptides to CD4 positive T cells. The blocking function of Ii helps prevent unwanted peptides from binding to class II molecules before they reach the endosomal compartment where they can properly bind and present antigens to T cells. Therefore, choice B is the correct answer. Ii does not impact the binding of antibody molecules or class I molecules to peptides, nor does it affect T cell receptors directly.

The Purpose of the Invariant Chain (Ii,CD74)is to Block the Peptide-Binding