Limited induction of polyfunctional lung-resident memory T cells against SARS-CoV-2 by mRNA vaccination compared to infection

Abstract

SARS-CoV-2; T cells; Vaccines

SARS-CoV-2; Células T; Vacunas

SARS-CoV-2; Cèl·lules T; Vacunes

Resident memory T cells (TRM) present at the respiratory tract may be essential to enhance early SARS-CoV-2 viral clearance, thus limiting viral infection and disease. While long-term antigen-specific TRM are detectable beyond 11 months in the lung of convalescent COVID-19 patients, it is unknown if mRNA vaccination encoding for the SARS-CoV-2 S-protein can induce this frontline protection. Here we show that the frequency of CD4+ T cells secreting IFNγ in response to S-peptides is variable but overall similar in the lung of mRNA-vaccinated patients compared to convalescent-infected patients. However, in vaccinated patients, lung responses present less frequently a TRM phenotype compared to convalescent infected individuals and polyfunctional CD107a+ IFNγ+ TRM are virtually absent in vaccinated patients. These data indicate that mRNA vaccination induces specific T cell responses to SARS-CoV-2 in the lung parenchyma, although to a limited extend. It remains to be determined whether these vaccine-induced responses contribute to overall COVID-19 control.

This work was supported by grants from Fundació La Marató TV3 (201814-10 FMTV3 and 202112-30 FMTV3, M.G.), from the Health department of the Government of Catalonia (DGRIS 1_5, to M.G. and M.J.B). M.J.B. is supported by the Miguel Servet program funded by the Spanish Health Institute Carlos III (CP17/00179).