Cytomegalovirus pp65 and IE-1 peptide–HLA class I complexes (CMV pp65/IE-1–HLA-I)

Cytomegalovirus (CMV) pp65 and IE-1 peptide–HLA class I complexes are molecular assemblies on the surface of infected host cells that serve as the primary recognition signals for the adaptive immune system (PubMed: 15507525). The pp65 protein (UL83) is the most abundant tegument protein and a dominant target for CD8+ T-cell responses, while the Immediate-Early 1 (IE-1) protein is crucial for viral replication and is expressed shortly after infection (UniProt: P06725, P13202). These viral proteins are processed into peptides and presented by Human Leukocyte Antigen (HLA) class I molecules, such as HLA-A*02:01, to cytotoxic T lymphocytes (CTLs). In clinical settings, these complexes are targeted by adoptive T-cell therapies and vaccines to restore or enhance CMV-specific immunity in immunocompromised patients, such as those undergoing hematopoietic stem cell transplantation (PubMed: 28232461). Recognition of these complexes by T-cell receptors (TCRs) triggers the destruction of the infected cell, making them pivotal for controlling viral latency and reactivation (NIH: PMC4133998). Furthermore, the development of TCR-engineered T cells and TCR-like antibodies specifically targeting these pMHC complexes represents a promising frontier in precision immunotherapy for CMV-related complications (PubMed: 30249041). These therapies aim to bypass the need for endogenous T-cell priming, providing immediate protection against viral dissemination in high-risk patients.

Other names

CMV pp65/IE-1 pMHCUL83/UL123-HLA class I complexCMV peptide-HLA complexCytomegalovirus antigen-MHC complexes

Recognition by T-cell receptors (TCRs) on CD8+ T cells leading to cytotoxic activity; induction of active immunity via vaccination; direct targeting by TCR-like antibodies or engineered T cells.