Leukemia-associated peptide-human leukocyte antigen complex (pHLA)

Leukemia-associated peptide-human leukocyte antigen (pHLA) complexes are molecular assemblies found on the surface of malignant hematopoietic cells, consisting of a short peptide fragment derived from intracellular proteins bound to an HLA molecule. These complexes serve as the primary mechanism for the immune system to monitor intracellular health, presenting fragments of leukemia-associated antigens (LAAs) such as WT1, PRAME, or mutated neoantigens to T-cells (Source: PubMed, PMID: 31515463). Because many leukemia-driving proteins are located within the cell and are not accessible to conventional monoclonal antibodies, these pHLA complexes are critical targets for next-generation immunotherapies (Source: Nature Reviews Cancer, TCR-based therapies for hematological malignancies). Therapeutic strategies include T-cell receptor (TCR)-engineered T-cells, TCR-mimetic antibodies, and bispecific molecules designed to recognize the specific peptide-HLA interface with high affinity (Source: NIH/NCI). By targeting these complexes, therapies can achieve high specificity for leukemic cells, potentially reducing systemic toxicity compared to traditional chemotherapy. However, challenges such as HLA downregulation by tumor cells and potential cross-reactivity with similar peptides on healthy tissues remain significant hurdles in clinical development (Source: PubMed, PMID: 33616161).

Other names

Peptide-major histocompatibility complexpMHCTumor-associated antigen-HLA complexLeukemia-specific peptide-HLA complexAntigen-presenting HLA complex

Recognition by T-cell receptors (TCRs) or TCR-mimetic antibodies leading to T-cell mediated cytotoxicity and apoptosis of the target cell.