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PubMed · 40964019

SARS-CoV-2 infection and vaccination elicit distinct pharyngeal mucosal B cell responses in children.

Abstract

Mucosal immunity is an important correlate of protection against respiratory infections such as SARS-CoV-2. Comparing B cell responses in the upper respiratory tract following vaccination and infection may offer unique insights into mucosal immunity. Here, we characterized antigen-specific B cells in the tonsils, adenoids, and peripheral blood of children who had been infected with SARS-CoV-2 or vaccinated with SARS-CoV-2 mRNA vaccines. SARS-CoV-2-specific switched memory B cells (BSM) and germinal center B cells were found in the blood and pharyngeal lymphoid tissues after vaccination or infection. However, infection generated a higher proportion of IgA+ BSM and CXCR3+CD21+ BSM, which showed distinct spatial localization, greater clonal expansion and increased propensity for plasma cell differentiation compared to their CXCR3- counterparts, accompanied by persistent activation of innate and T follicular helper cells in the tissues. Our data provide evidence for tissue-specific B cell memory after either SARS-CoV-2 vaccination or infection, but with distinct characteristics that can influence the quality, durability, and localization of immunity.

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Kalpana Manthiram, Qin Xu, Lihong Shi, Liya Wang, Foo Cheung, Aparna Kotekar, Galina Koroleva, Elizabeth Rice, Richard Apps, Justin Lack, Craig Martens, Iyadh Douagi, Can Liu, Juraj Kabat, Hengameh Behzadpour, Lela Kardava, Tovah Markowitz, Margery Smelkinson, Kenneth Hoehn, Clarisa Buckner, Dominic Golec, Lorenza Bellusci, Gabrielle Grubbs, Sara Pourhashemi, Juanjie Tang, Asya Khleborodova, Martha Kirby, Rachel Sparks, Andrew Martins, John Tsang, Susan Moir, Surender Khurana, Pamela Mudd, Pamela Schwartzberg. 2025-09-09. SARS-CoV-2 infection and vaccination elicit distinct pharyngeal mucosal B cell responses in children.. https://doi.org/10.21203/rs.3.rs-7428491%2Fv1

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