Invitrogen™ MHC Class II (H2-Aa) Polyclonal Antibody

MHC class II molecules are heterodimers of non-covalently associated alpha (31-34 kDa) and beta (26-29 kDa) chains. Major histocompatibility complex class II antigen presentation requires the participation of lysosomal proteases in two convergent processes. First, the antigens endocytosed by the antigen presenting cells must be broken down into antigenic peptides. Second, class II molecules are synthesized with their peptide-binding site blocked by invariant chain (Ii), and they aquire the capacity to bind antigens only after Ii has been degraded in the compartments where peptides reside. MHC class II molecules present exogenously derived antigen to CD4+ T lymphocytes, which are usually T helper cells. CD4 interacts with non-polymorphic residues of MHC class II. HLA and MHC antibodies play a significant role in Immunopeptidomics, facilitating the identification and characterization of neoantigens through high-performance liquid chromatography coupled to tandem Mass Spectrometry.