Cross-reactive cellular, but not humoral, immunity is detected between OC43 and SARS-CoV-2 NPs in people not infected with SARS-CoV-2: Possible role of cTFH cells.

Abstract

Multiple questions about SARS-CoV-2 humoral and cellular immunity remain unanswered. One key question is whether preexisting memory T or B cells, specific for related coronaviruses in SARS-CoV-2-unexposed individuals, can recognize and suppress COVID-19, but this issue remains unclear. Here, we demonstrate that antibody responses to SARS-CoV-2 antigens are restricted to serum samples from COVID-19 convalescent individuals. In contrast, cross-reactive T cell proliferation and IFN-γ production responses were detected in PBMCs of around 30% of donor samples collected prepandemic, although we found that these prepandemic T cell responses only elicited weak cTFH activation upon stimulation with either HCoV-OC43 or SARS-CoV-2 NP protein. Overall, these observations confirm that T cell cross-reactive with SARS-CoV-2 antigens are present in unexposed people, but suggest that the T cell response to HCoV-OC43 could be deficient in some important aspects, like TFH expansion, that might compromise the generation of cross-reactive TFH cells and antibodies. Understanding these differences in cellular responses may be of critical importance to advance in our knowledge of immunity against SARS-CoV-2.

• Authors: Álvaro Fernando García-Jiménez, Yaiza Cáceres-Martell, Daniel Fernández-Soto, Pedro Martínez Fleta, José M Casasnovas, Francisco Sánchez-Madrid, José Miguel Rodríguez Frade, Mar Valés-Gómez, Hugh T Reyburn
• Journal: Journal of leukocyte biology (J Leukoc Biol) Vol. 112 Issue 2 Pg. 339-346 (08 2022) ISSN: 1938-3673 [Electronic] England
• PMID: 35384035 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2022 The Authors. Journal of Leukocyte Biology published by Wiley Periodicals LLC on behalf of Society for Leukocyte Biology.

Chemical References

• Antibodies, Viral

Topics

• Antibodies, Viral
• COVID-19
• Coronavirus OC43, Human
• Cross Reactions
• Humans
• Immunity, Humoral
• SARS-CoV-2