Table 2.

MHC class II effects on FV immunity

(1) H-2E molecules are not expressed on the cell surface in H-2^b mice because of lack of a functional E α gene (46, 47). (2) H-2E α chains form the k haplotype associate with β chains from the b haplotype to form functional cell surface heterodimers that present F-MuLV envelope peptides to CD4⁺ T cells (48). H-2E^k/k molecules may affect the FV-specific immune response also, but their role is unknown.