HLA class I histocompatibility antigen, A-23 alpha chain (HLA-A23)

HLA class I histocompatibility antigen, A-23 alpha chain (HLA-A23) is a specific allele of the human leukocyte antigen (HLA) class I heavy chain, which forms a heterodimer with beta-2 microglobulin to present endogenous peptides to CD8+ cytotoxic T lymphocytes (UniProt: P01892). As a member of the HLA-A9 serotype group, HLA-A23 plays a pivotal role in the adaptive immune system by enabling the surveillance of intracellular pathogens and mutated proteins (IMGT/HLA Database). It is particularly significant in the context of infectious diseases, such as HIV-1, where specific HLA-A23-restricted epitopes influence viral control and disease progression; for instance, the HLA-A*23:01 allele has been linked to faster progression to AIDS in certain cohorts (PMID: 15146178). In oncology, HLA-A23 serves as a restriction element for the development of TCR-T cell therapies and peptide vaccines, allowing for the targeted destruction of cancer cells that present specific neoantigens (PMID: 25605930). However, its high polymorphism and role in self-nonself recognition make it a primary target for immune-mediated rejection in organ and hematopoietic stem cell transplantation (NIH: HLA-A). Consequently, therapeutic strategies involving HLA-A23 often focus on either suppressing the immune response with drugs like Tacrolimus to prevent graft rejection or harnessing its presentation capabilities to enhance anti-tumor immunity.

Other names

HLA-A*23MHC class I antigen A*23HLA-A23Human leukocyte antigen A23HLA-A*23:01

Presentation of intracellular peptides to CD8+ T cells; targeted by immunosuppressants to prevent T-cell mediated rejection or by TCR-T cells to induce tumor lysis.