Minor histocompatibility antigen HA-2 peptide–HLA-A*02:01 complex (HA-2–HLA-A*02:01)

The HA-2 peptide–HLA-A*02:01 complex is a specific peptide-major histocompatibility complex (pMHC) that serves as a target for immunotherapy in hematologic malignancies (PubMed: 10508251). The HA-2 peptide is a minor histocompatibility antigen (mHAg) derived from the MYO1G gene, which is predominantly expressed in hematopoietic cells (UniProt: Q13352). When presented by the HLA-A*02:01 allele, this complex can be recognized by cytotoxic T lymphocytes (CTLs), triggering an immune response (PubMed: 15128758). This interaction is particularly significant in the context of allogeneic hematopoietic stem cell transplantation, where it contributes to the graft-versus-leukemia (GvL) effect. Therapeutic approaches include the development of TCR-engineered T cells and peptide-based vaccines designed to selectively eliminate leukemic cells while minimizing systemic toxicity (PubMed: 21670471). However, because HA-2 is a minor histocompatibility antigen, its mismatch between donor and recipient can also lead to graft-versus-host disease (GvHD) (PubMed: 9580016).

Other names

HA-2/HLA-A2 complexMYO1G-derived peptide–HLA-A*02:01Minor histocompatibility antigen HA-2YIGEVLVSV–HLA-A*02:01

Targeted lysis of HA-2-expressing cells by T cells through specific recognition of the peptide-MHC complex by T-cell receptors (TCRs).