HLA class II histocompatibility antigen DRB1-04 beta chain (HLA-DRB1*04)

The HLA class II histocompatibility antigen DRB1-04 beta chain is a critical component of the human leukocyte antigen (HLA) system, specifically the MHC class II complex. It forms a heterodimer with the HLA-DRA alpha chain to present exogenous peptide antigens to CD4+ T helper cells, thereby initiating and regulating adaptive immune responses [1, 18]. This specific beta chain variant is encoded by the HLA-DRB1*04 allele and is characterized by a 'shared epitope' sequence in its peptide-binding groove, which is the most significant genetic risk factor for rheumatoid arthritis [1, 8]. Beyond rheumatoid arthritis, it is associated with various autoimmune conditions, including type 1 diabetes and multiple sclerosis, where it likely facilitates the presentation of self-antigens [2, 3]. In clinical practice, the presence of this target influences the therapeutic efficacy of drugs like abatacept and cyclosporine, making it a vital biomarker for personalized medicine [7, 17]. Therapeutic strategies targeting this molecule focus on blocking its peptide-binding groove or modulating the downstream T-cell activation to restore immune tolerance [8, 20].

Other names

HLA-DRB1*04DR4MHC class II antigen DRB1*04HLA-DR1BSS1Major histocompatibility complex class II DR beta 1

Co-stimulation blockade, competitive MHC II binding, calcineurin inhibition, and modulation of antigen presentation