Conserved CD8 T cell vaccines without B cell epitopes drive robust protection against SARS-CoV-2 that is enhanced by intranasal boost.

ABSTRACT: The emergence of SARS-CoV-2 variants has challenged the current spike protein-focused COVID-19 vaccine strategy due to neutralizing antibody escape and waning antibody-mediated immunity. In contrast, T cell-mediated immunity targeting conserved epitopes may offer broad and long-lasting protection. However, whether T cells alone can provide sufficient protection remains unclear. Here, we identified both Omicron BA.1-specific and ancestral (Wuhan)-conserved CD8 T cell epitopes in the SARS-CoV-2 spike protein and evaluated them as carrier-protein fusion vaccines in mouse models. Subcutaneous immunizations with two CD8 epitope peptides substantially lowered lung viral load and conferred protection against low-dose viral challenge, but not against high-dose challenge. Notably, intranasal boosti

SUBMITTER: Chen G 

PROVIDER: S-EPMC12637294 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature