Immune system. Introduction.
D001402:B-Lymphocytes / Q000276:immunology*; D005802:Genes, MHC Class II; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D009369:Neoplasms / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
D000949:Histocompatibility Antigens Class II