SARS-CoV-2-specific CD4+ T cells are likely important in immunity against COVID-19, but our understanding of CD4+ longitudinal dynamics following infection, and specific features that correlate with the maintenance of neutralizing antibodies, remains limited. Here, we characterize SARS-CoV-2-specific CD4+ T cells in a longitudinal cohort of 109 COVID-19 outpatients enrolled during acute infection. The quality of the SARS-CoV-2-specific CD4+ response shifts from cells producing IFNγ to TNFα from five days to four months post-enrollment, with IFNγ–IL21–TNFα+ CD4+ T cells the predominant population detected at later timepoints. Greater percentages of IFNγ–IL21–TNFα+ CD4+ T cells on day 28 correlate with SARS-CoV-2 neutralizing antibodies measured seven months post-infection (⍴=0.4, P=0.01). mRNA vaccination following SARS-CoV-2 infection boosts both IFNγ and TNFα producing, spike protein-specific CD4+ T cells. These data suggest that SARS-CoV-2-specific, TNFα-producing CD4+ T cells may play an important role in antibody maintenance following COVID-19.
Fuente: Cell Reports Medicine
Available online 3 May 2022, 100640