Wang 2024 identified 3 N-protein CD8+ T-cell epitopes that were conserved between SARS-CoV and SARS-CoV-2:
- Epitope N262-270: Conserved between SARS-CoV-2 and SARS-CoV with a single substitution (K→Q at position 266).
- Retains structural similarity, allowing cross-reactivity
- Epitope N266-274: Conserved between SARS-CoV-2 and SARS-CoV with a single substitution (A→Q at position 267).
- High conservation of binding regions
- Shown to be presented by multiple HLA alleles, enabling broader population coverage.
- Epitope N261-277: Minor variations between SARS-CoV and SARS-CoV-2 forms
- Retained cross-reactivity
- Stimulates both CD4+ and CD8+ T cells.
- Recognized across diverse HLA types
Meyer 2023 identified 7 non-spike CD8+ T-cell epitopes conserved across all SARS-CoV-2 variants of concern tested.
- N262-270, N266-274, N261-277
- M105-113
- ORF3a(206-215), ORF3a*203-212), ORF3a(139-147)