Cytomegalovirus peptide–Major Histocompatibility Complex class I (CMV pMHC-I) (CMV pMHC-I)

Cytomegalovirus (CMV) peptide–Major Histocompatibility Complex (MHC) class I complexes are essential molecular structures for the cellular immune response against CMV. These complexes consist of an 8-11 amino acid viral peptide, typically derived from highly immunogenic proteins like pp65 (UL83) or IE1 (UL123), nested within the peptide-binding groove of a host MHC class I molecule (HLA in humans) (PubMed: 15140877). They are expressed on the surface of infected cells, serving as the primary signal for recognition and destruction by CD8+ cytotoxic T-lymphocytes (CTLs) (PubMed: 28630411). In clinical settings, these complexes are targeted by adoptive T-cell therapies and vaccines to restore or enhance CMV-specific immunity, particularly in hematopoietic stem cell or solid organ transplant recipients (ClinicalTrials.gov: NCT02303730). Therapeutic strategies include the infusion of donor-derived or off-the-shelf CMV-specific T-cells, such as Viralym-M, and the development of TCR-like antibodies that mimic the specificity of the immune system (AlloVir). These complexes are critical for controlling viral reactivation, which remains a significant cause of morbidity in immunocompromised populations.

Other names

CMV pMHCHLA-restricted CMV peptide complexCMV antigen-MHC complexCytomegalovirus peptide-HLA complex

Recognition by T-cell receptors (TCRs) to trigger cytotoxic T-lymphocyte (CTL) mediated lysis of infected cells (PubMed: 28630411).