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Isolation of Tonsillar Mononuclear Cells to Study Ex Vivo Innate Immune Responses in a Human Mucosal Lymphoid Tissue
Published on: June 14, 2020
Tonsils are major sites of persistence of SARS-CoV-2 in children
Thais Melquiades de Lima1, Ronaldo Bragança Martins1,2, Carolina Sponchiado Miura3
1Department of Cellular and Molecular Biology and Pathogenic Bioagents, University of São Paulo School of Medicine , Ribeirão Preto, São Paulo, Brazil.
Importance:
This study shows that SRS-CoV-2 of different lineages can infect tonsils and adenoids in one quarter of children undergoing tonsillectomy. These findings bring advancement to the area of SARS-CoV-2 pathogenesis, by showing that tonsils may be sites of prolonged infection, even without evidence of recent COVID-19 symptoms. SARS-CoV-2 infection of B and T lymphocytes, macrophages, and dendritic cells may interfere with the mounting of immune responses in these secondary lymphoid organs. Moreover, the shedding of SARS-CoV-2 RNA in respiratory secretions from silently infected children raises concern about possible diagnostic confusion in the presence of symptoms of acute respiratory infections caused by other etiologies.
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