Human class II MHC Ag are a family of cell surface glycoproteins .
human class ii mhc ag are a family of cell surface glycoproteins .
B-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group O O O O B-protein_domain_or_region I-protein_domain_or_region I-protein_domain_or_region O