Human leukocyte antigen (HLA) (HLA)

Human leukocyte antigen (HLA) molecules are a group of cell surface proteins encoded by the Major Histocompatibility Complex (MHC) gene family in humans (StatPearls, 2023). Their primary biological function is to present processed peptide fragments to T-cell receptors, thereby initiating and regulating the adaptive immune response (NIH, 2024). In the context of clinical medicine, recipient HLA molecules are the primary targets of the donor's immune system in graft-versus-host disease (GVHD), where donor T-cells recognize recipient HLA as foreign (Frontiers in Immunology, 2021). Furthermore, specific recipient HLA alleles are strongly associated with drug hypersensitivity reactions, where medications like abacavir bind to the HLA groove and trigger an inappropriate immune response (Nature Reviews Immunology, 2012). Therapeutic strategies involving HLA often focus on immunosuppression to prevent T-cell recognition or desensitization protocols to reduce pre-existing anti-HLA antibodies (DrugBank, 2024). Understanding the HLA profile of a recipient is essential for predicting transplant outcomes and avoiding severe adverse drug reactions.

Other names

Major Histocompatibility ComplexMHCHuman MHCHLA complex

Direct binding to the peptide-binding groove to alter peptide presentation or inhibition of costimulatory signals required for HLA-mediated T-cell activation.