Virus-infected cells presenting viral antigens

Virus-infected cells presenting viral antigens are host cells that have been compromised by a virus and are subsequently flagged for destruction by the adaptive immune system. These cells process intracellular viral proteins into small peptides and display them on their surface via Major Histocompatibility Complex (MHC) Class I molecules (StatPearls, 2021). This presentation allows CD8+ cytotoxic T lymphocytes (CTLs) to recognize the cell as infected and initiate programmed cell death through the release of cytotoxic granules like perforin and granzymes (Journal of Virology, 2008). In modern drug development, this biological state is targeted by immunotherapies such as TCR-engineered T cells and bispecific T-cell engagers (BiTEs), which are designed to bind specifically to these MHC-peptide complexes to eliminate the viral reservoir (Scientific Archives, 2021). However, many viruses have evolved evasion strategies, such as the downregulation of MHC molecules or the mutation of immunodominant epitopes, which pose significant challenges to therapeutic efficacy (Nature Reviews Immunology, 1999). Additionally, a major safety concern in targeting these cells is the potential for off-target toxicity if the therapeutic agent cross-reacts with similar self-peptides presented on healthy tissues.

Other names

Infected host cellsAntigen-presenting infected cellsMHC-peptide complexesVirally infected cellspMHC-presenting cells

Therapies targeting these cells utilize engineered T-cell receptors (TCRs) or bispecific antibodies to recognize specific viral peptides presented by MHC Class I molecules, triggering cytotoxic T-lymphocyte mediated lysis of the infected cell via the release of perforin and granzymes.