Major histocompatibility complex, class II, DR beta 3 (HLA-DRB3)

Major histocompatibility complex, class II, DR beta 3 (HLA-DRB3) is a membrane-anchored beta chain that pairs with an alpha chain (HLA-DRA) to form a heterodimeric class II MHC molecule, primarily expressed in professional antigen-presenting cells such as B cells, dendritic cells, and monocytes[1][4][5][6]. HLA-DRB3 plays a central role in the immune system by presenting peptides derived from extracellular proteins for recognition by CD4+ T cells, and it contributes to shaping the repertoire of the adaptive immune response[5][6]. Variation in DRB3 alleles modulates disease susceptibility, transplantation outcomes, and immune tolerance, underpinning its relevance as a genetic biomarker and immunological target. The structural diversity of its peptide-binding groove underlies its disease associations and immunological specificity, especially for certain autoimmune and alloimmune pathologies[2][3][8]. If further structured or specific data fields are needed, such as gene IDs or protein accession codes, these can be obtained from gene/protein databases (e.g., NCBI Gene ID 3125; UniProt P79483)[1][5][6].

Other names

HLA-DRB3DRB3DR52HLA-DR3BDRB3_HUMANDR52a/DR52b/DR52c

Presentation of peptide antigens to CD4+ T lymphocytes, initiating adaptive immune responses. Drug action occurs indirectly via systemic immunosuppression, T cell depletion, or tolerance induction, rather than direct modulation of HLA-DRB3.