The rat monoclonal antibody M5/114 reacts with murine MHC class II glycoproteins. It recognizes a shared extracellular determinant on I-Ab, I-Ad, I-Aq, and I-Ed, I-Ek alloantigens, but it does not react with I-Af, I-Ak, I-As. This antibody can inhibit I-A-restricted T cell responses of the H-2b, H-2d, H-2q, H-2u but not H-2f, H-2k, H-2s haplotypes.
Purification
Purified antibody is conjugated with biotin LC-NHS ester under optimum conditions and unconjugated antibody and free biotin are removed by size-exclusion chromatography.
MHC (major histocompatibility complex) class II molecules are transmembrane glycoproteins expressed on the surface of professional antigen-presenting cells, such as macrophages, dendritic cells and B cells. Before their exposition on the cell surface, the MHC class II molecules react with endocytosed exogenous antigens, which are then presented to the T cells. The antigen-binding grove between MHC class II alpha and beta chain is open at both ends and is 15-24 amino acid residues long.