Human Major Histocompatibility Complex (MHC) class I and II presentation of SARS-CoV-2 T-cell epitopes (HLA-SARS-CoV-2 presentation)

The presentation of SARS-CoV-2 T-cell epitopes by Human Major Histocompatibility Complex (MHC) class I and II molecules is the central mechanism by which the adaptive immune system recognizes and responds to COVID-19 infection. MHC class I molecules (HLA-A, -B, -C) present endogenous viral peptides, primarily from the Spike, Nucleocapsid, and Membrane proteins, to CD8+ cytotoxic T cells to eliminate infected cells [1: Grifoni et al., Cell, 2020]. MHC class II molecules (HLA-DR, -DQ, -DP) present exogenous viral fragments to CD4+ helper T cells, which are essential for orchestrating B-cell antibody responses and long-term immune memory [2: Sette and Crotty, Cell, 2021]. The efficiency and breadth of this presentation are heavily influenced by an individual's HLA polymorphism, which can determine disease severity and the effectiveness of vaccination [3: Nguyen et al., J Virol, 2020]. Current therapeutic interventions, such as mRNA and viral vector vaccines, are designed to exploit this pathway by delivering genetic instructions that lead to the intracellular production and subsequent MHC presentation of viral antigens [4: Sahin et al., Nature, 2020]. Monitoring this process through T-cell assays and HLA typing is critical for evaluating vaccine efficacy and the potential for viral escape via epitope mutations [5: Tarke et al., Cell Rep Med, 2021]. [6: Nelde et al., Nat Immunol, 2021].

Other names

MHC-restricted SARS-CoV-2 antigen presentationHLA presentation of COVID-19 epitopesT-cell epitope presentation of SARS-CoV-2HLA-restricted T-cell epitope presentation

Vaccines deliver antigens or genetic sequences that are processed into peptides and loaded onto MHC class I and II molecules for presentation to T-cell receptors (TCRs), thereby priming the adaptive immune system.