Introduction
Results
Identification of human HLA-I epitope-enriched regions in the SARS-CoV-2 proteome
The class I human leukocyte antigen (HLA-I) complex shows high polymorphism, resulting in the broad diversity of CD8+ T-lymphocyte epitopes among human individuals23. We aimed to identify regions with diverse HLA-I-specific epitopes throughout SARS-CoV-2 open reading frames (ORFs), thus enabling the development of a recombinant antigen that induces broad and potent virus-specific responses by cytotoxic T lymphocytes (CTLs) (Fig.
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Assessment of the immunogenicity of HLA-I epitope-enriched peptides in humanized HLA-transgenic mice
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Dual immunization with HLA-EPs and SARS-CoV-2 RBD antigens protects humanized HLA-transgenic mice from infection with SARS-CoV-2 variants
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Dual immunization with HLA-EPs and a SARS-CoV-2 RBD produces optimal protection against SARS-CoV-2 in nonhuman primates
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Discussion
The previous study revealed that the T-cell responses in individuals with prior infection and vaccination are largely preserved to Omicron Spike and several nonspike proteins. Nonetheless, a subset of individuals has a more than 50% reduction in T-cell reactivity to the Omicron Spike22