HLA Class I-A Recombinant Mouse mAb (S-3834)

Human Leukocyte Antigen Class I-A molecules (HLA Class I-A, typically referring to the classical HLA-Ia molecules: HLA-A, HLA-B, and HLA-C) are core members of the Major Histocompatibility Complex (MHC) Class I family, widely expressed on the surface of nearly all nucleated cells. Their primary function is to serve as critical immunological "identity cards" for immune surveillance by binding short peptide fragments (typically 8–10 amino acids) derived from intracellular proteins—including self-proteins, viral proteins, or tumor mutation products—and presenting them on the cell surface for specific recognition by CD8+ cytotoxic T lymphocytes (CTLs) via their T-cell receptors (TCRs). Structurally, these molecules consist of a transmembrane heavy chain (α-chain, encoded by highly polymorphic HLA genes that determine peptide-binding specificity and individual differences in transplant rejection) non-covalently associated with a non-polymorphic light chain (β2-microglobulin, β2m). This architecture not only ensures normal self-cells are spared from attack (by transmitting "self" signals through inhibitory receptors such as KIRs or LILRB1) but also triggers CTL-mediated lysis of target cells when they are infected by viruses or undergo malignant transformation through the presentation of abnormal antigenic peptides. Consequently, HLA Class I-A molecules play an indispensable and decisive role in antiviral immunity, anti-tumor immunity, and the matching and rejection processes in organ transplantation.