The HLA-DRA antibody targets the alpha chain of the HLA-DR antigen, a major histocompatibility complex (MHC) class II molecule critical for adaptive immune responses. HLA-DRA, encoded by the HLA-DRA gene on chromosome 6. pairs with HLA-DRB chains to form heterodimers that present exogenous antigens to CD4+ T cells, initiating immune activation. Unlike HLA-DRB chains, HLA-DRA exhibits limited polymorphism, contributing to structural stability rather than antigen-binding specificity.
Antibodies against HLA-DRA are widely used in research to study MHC class II expression patterns in immune-related diseases. Dysregulated HLA-DR expression is implicated in autoimmune disorders (e.g., rheumatoid arthritis, lupus), infections, and cancers. For example, reduced HLA-DR on antigen-presenting cells may correlate with immunosuppression in sepsis or tumor microenvironments. Conversely, overexpression is linked to autoimmune inflammation.
These antibodies enable detection via techniques like flow cytometry, immunohistochemistry, or Western blot, aiding in diagnostics and mechanistic studies. They also help explore HLA-DRA's role in transplant rejection, as MHC class II mismatches drive donor-specific immune responses. Additionally, HLA-DRA antibodies are tools for investigating transcriptional regulation of MHC genes, such as CIITA-mediated pathways. Their applications extend to therapeutic development, including checkpoint inhibitors or vaccines targeting HLA-DR-restricted antigens.