Cytomegalovirus phosphoprotein 65 peptide-Major Histocompatibility Complex (CMV pp65-pMHC)

The Cytomegalovirus (CMV) phosphoprotein 65 (pp65) peptide-Major Histocompatibility Complex (pMHC) is a primary immunological target for managing CMV infections, particularly in immunocompromised patients such as transplant recipients (Stern et al., 2019, PMID: 31141623). pp65, encoded by the UL83 gene, is the most abundant tegument protein of the virus and is highly immunogenic (UniProtKB - P06725). During the viral life cycle, pp65 is processed into peptides that are presented on the cell surface by MHC Class I molecules to CD8+ T cells or MHC Class II molecules to CD4+ T cells (Arvin et al., 2004, PMID: 15650022). This presentation allows the immune system to identify and eliminate infected cells through T-cell receptor (TCR) recognition. Therapeutic interventions targeting this complex include adoptive T-cell therapies, such as posoleucel, and various peptide or viral vector vaccines like Triplex (AlloVir, 2023). Because pp65 is a non-human viral protein, it serves as a highly specific target with a low risk of autoimmune cross-reactivity, though CMV's ability to downregulate MHC molecules presents a challenge for therapeutic efficacy (Reddehase, 2002, PMID: 12117117).

Other names

CMV UL83 peptide-MHC complexpp65-HLA complexCytomegalovirus pp65 epitope-MHCCMV pp65-MHC Class I complexCMV pp65-MHC Class II complex

Recognition by T-cell receptors (TCRs) on cytotoxic T lymphocytes (CTLs) or helper T cells, leading to targeted lysis of infected cells and the production of antiviral cytokines.