SARS-CoV-2 nucleoprotein (N protein)

The SARS-CoV-2 nucleoprotein (N protein) is a highly conserved structural protein essential for the viral life cycle, primarily responsible for packaging the viral RNA genome into a helical ribonucleoprotein complex (UniProt P0DTC9). Unlike the Spike protein, the N protein is less prone to mutations, making its antigenic peptides ideal targets for inducing long-lasting and cross-reactive T-cell immunity (Le Bert et al., 2020, Nature). CD8+ T-cell receptors (TCRs) recognize specific N-derived peptides, such as the conserved N105-113 epitope, when presented by Major Histocompatibility Complex (MHC) Class I molecules on the surface of infected cells (Grifoni et al., 2020, Cell Host & Microbe). This interaction triggers a cytotoxic response that eliminates viral factories, providing a critical defense mechanism that complements antibody-mediated immunity. Therapeutic strategies focusing on these conserved peptides include next-generation vaccines (e.g., Gritstone's GRT-R910) and TCR-engineered T-cell therapies designed to provide protection against emerging variants of concern (Gritstone Bio, 2022). By targeting the N protein, these therapies aim to overcome the limitations of Spike-centric vaccines, which are more susceptible to viral escape (Vaxart, 2021).

Other names

Nucleocapsid proteinSARS-CoV-2 N proteinNCAP_SARS2Protein N

Induction of cellular immunity through the presentation of conserved viral peptides on MHC Class I molecules to CD8+ T-cell receptors, leading to the destruction of infected cells.