What holds the small peptide fragments of an antigen at the surface of an APC?
A)phosphotyrosine motifs
B)MHC proteins
C)T-cell receptors
D)phosphatidylinositol
E)B-cell receptors

Question

Quizplus · Accepted Answer

MHC proteins hold the small peptide fragments of an antigen at the surface of an APC (antigen-presenting cell). MHC stands for major histocompatibility complex, and these proteins are responsible for presenting antigens to T cells. There are two classes of MHC proteins: MHC class I presents antigens to CD8+ T cells, while MHC class II presents antigens to CD4+ T cells. The peptide fragments of the antigen bind to a groove on the MHC protein and are presented on the surface of the APC for recognition by T cells.

What Holds the Small Peptide Fragments of an Antigen at the Surface