Cytomegalovirus 65 kDa phosphoprotein (pp65) peptide-HLA class II complex (CMV pp65-HLA-II)

The Cytomegalovirus 65 kDa phosphoprotein (pp65) peptide-HLA class II complex is a critical immunological target formed when the pp65 protein (UniProt: P06725) is processed and presented on the surface of antigen-presenting cells (PubMed: 15604144). This complex is specifically recognized by the T-cell receptors (TCRs) of CD4+ T-helper cells, which play a pivotal role in orchestrating the adaptive immune response against CMV (PubMed: 28963471). In healthy individuals, this interaction maintains viral latency, but in immunocompromised patients, such as those undergoing hematopoietic stem cell or solid organ transplantation, the failure of this recognition leads to life-threatening CMV reactivation (PubMed: 10807514). Therapeutic strategies targeting this complex include adoptive cell therapies like Posoleucel (ALVR105), where CMV-specific T cells are expanded ex vivo and infused into patients to restore immunity (ClinicalTrials.gov: NCT04354805). Additionally, vaccines and TCR-based biologics are being developed to enhance the detection of these epitopes. Monitoring the presence of these complexes and the corresponding T-cell response is essential for managing post-transplant complications and ensuring long-term viral control (PubMed: 16210402).

Other names

CMV pp65-MHC class II complexUL83-derived peptide-HLA class IICMV pp65-HLA-DR complexCMV pp65-HLA-DQ complexCMV pp65-HLA-DP complex

Recognition by T-cell receptors (TCRs) on CD4+ T-helper cells, leading to immune activation and viral clearance (PubMed: 28963471).