SARS-CoV-2 spike peptide–Major Histocompatibility Complex (SARS-CoV-2 spike–MHC) (SARS-CoV-2 spike–MHC)

SARS-CoV-2 spike peptide–Major Histocompatibility Complex (MHC) complexes are molecular assemblies formed when fragments of the SARS-CoV-2 spike protein are processed and presented on the surface of host cells [1]. These complexes are the fundamental units recognized by the cellular arm of the adaptive immune system, where MHC Class I-bound peptides activate CD8+ cytotoxic T-cells and MHC Class II-bound peptides activate CD4+ helper T-cells [2]. This recognition is crucial for the elimination of virus-infected cells and the coordination of the overall immune response during COVID-19 infection [3]. Most current vaccines function by introducing the spike protein sequence, which is then expressed and presented as these peptide–MHC complexes to prime the immune system [4]. Understanding the structural and genetic diversity of these complexes is vital for addressing viral variants and ensuring broad population coverage in vaccine design [5]. These complexes also serve as critical targets for next-generation immunotherapies, such as TCR-engineered T-cells, which aim to provide protection even when neutralizing antibody titers are low [6].

Other names

SARS-CoV-2 S-peptide–HLA complexSpike protein–MHC complexSARS-CoV-2 epitope–MHC complexSARS-CoV-2 spike–HLA-I/II complex

Presentation of viral spike epitopes to T-cell receptors (TCRs) to initiate CD4+ and CD8+ T-cell mediated immunity; vaccines induce the formation of these complexes to prime the immune system [2, 3, 5].