Omicron BA.1 Mutations in SARS-CoV-2 Spike Lead to Reduced T-Cell Response in Vaccinated and Convalescent Individuals.

ABSTRACT: Omicron BA.1 variant can readily infect people with vaccine-induced or naturally acquired SARS-CoV-2 immunity facilitated by escape from neutralizing antibodies. In contrast, T-cell reactivity against the Omicron BA.1 variant seems relatively well preserved. Here, we studied the preexisting T cells elicited by either vaccination with the mRNA-based BNT162b2 vaccine or by natural infection with ancestral SARS-CoV-2 for their cross-reactive potential to 20 selected CD4⁺ T-cell epitopes of spike-protein-harboring Omicron BA.1 mutations. Although the overall memory CD4⁺ T-cell responses primed by the ancestral spike protein was still preserved generally, we show here that there is also a clear loss of memory CD4⁺ T-cell cross-reactivity to immunodominant epitop

SUBMITTER: Emmelot ME 

PROVIDER: S-EPMC9318964 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature