HIV-1 Trans-activator of transcription (Tat) peptide-MHC complex (HIV-1 Tat pMHC)

The HIV-1 Trans-activator of transcription (Tat) peptide-MHC complex is a critical immunological target for the control of HIV-1 infection. Tat is an early regulatory protein essential for viral gene expression and replication, making it an ideal target for eliminating infected cells before they produce large quantities of progeny virus (UniProt P04608). In infected cells, Tat is proteolytically processed into short peptides that are loaded onto Major Histocompatibility Complex (MHC) Class I molecules and transported to the cell surface. These peptide-MHC (pMHC) complexes are specifically recognized by the T-cell receptors (TCRs) of cytotoxic CD8+ T lymphocytes, which then initiate apoptosis in the target cell (PubMed: 26331179). Therapeutic interventions, such as TCR-engineered T-cell therapies and therapeutic vaccines, aim to exploit this mechanism to reduce the viral reservoir and achieve a functional cure (PubMed: 20445862). However, the high mutation rate of HIV-1 poses a significant challenge, as mutations within Tat epitopes can lead to immune escape, rendering the TCRs ineffective (PubMed: 25924318). Additionally, ensuring the specificity of engineered TCRs is vital to avoid cross-reactivity with host proteins, which could lead to severe autoimmune-like toxicities.

Other names

HIV-1 Tat antigenTat peptide-HLA complexTat pMHCHIV-1 Tat-derived peptide-MHCTat-MHC-TCR axis

Recognition of the peptide-MHC complex by T-cell receptors (TCRs) triggers the activation of cytotoxic T lymphocytes (CTLs), leading to the targeted lysis of HIV-infected cells.