This antibody reacts with the beta2-microglobulin (B2M) associated with cell-surface MHC Class I molecules and other membrane antigens as well as with soluble B2-microglobulin.
In the immunoprecipitation test the GRH1 two bands were precipitated on SDS-PAGE analysis of 43 kDa and 12 kDa corresponding to the heavy chain of the HLA-A, B and C antigens encoded by a gene on chromosome 6, and the beta 2-microglobulin which is a non-glycosylated protein noncovalently bound to the heavy chain that is encoded by a gene on chromosome 15 (Entrez Gene (human): 15q21-q22.2)