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Enhanced eosinophil-mediated inflammation associated with antibody and complement-dependent pneumonic insults in critical COVID-19.

ABSTRACT: Despite the worldwide effect of the coronavirus disease 2019 (COVID-19) pandemic, the underlying mechanisms of fatal viral pneumonia remain elusive. Here, we show that critical COVID-19 is associated with enhanced eosinophil-mediated inflammation when compared to non-critical cases. In addition, we confirm increased T helper (Th)2-biased adaptive immune responses, accompanying overt complement activation, in the critical group. Moreover, enhanced antibody responses and complement activation are associated with disease pathogenesis as evidenced by formation of immune complexes and membrane attack complexes in airways and vasculature of lung biopsies from six fatal cases, as well as by enhanced hallmark gene set signatures of Fcγ receptor (FcγR) signaling and complement activation in myeloid cells of respiratory specimens from critical COVID-19 patients. These results suggest that SARS-CoV-2 infection may drive specific innate immune responses, including eosinophil-mediated inflammation, and subsequent pulmonary pathogenesis via enhanced Th2-biased immune responses, which might be crucial drivers of critical disease in COVID-19 patients.

SUBMITTER: Kim DM

PROVIDER: S-EPMC8450316 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Enhanced eosinophil-mediated inflammation associated with antibody and complement-dependent pneumonic insults in critical COVID-19.

Kim Dong-Min DM Kim Yuri Y Seo Jun-Won JW Lee Jooyeon J Park Uni U Ha Na-Young NY Koh Jaemoon J Park Hyoree H Lee Jae-Won JW Ro Hyo-Jin HJ Yun Na Ra NR Kim Da Young DY Yoon Sung Ho SH Na Yong Sub YS Moon Do Sik DS Lim Sung-Chul SC Kim Choon-Mee CM Jeon Kyeongseok K Kang Jun-Gu JG Jang Na-Yoon NY Jeong Hyeongseok H Kim Jungok J Cheon Shinhyea S Sohn Kyung Mok KM Moon Jae Youg JY Kym Sungmin S Han Seung Ro SR Lee Myung-Shin MS Kim Hyun-Je HJ Park Woong-Yang WY Choi Ji-Yeob JY Shin Hyun-Woo HW Kim Hye-Young HY Cho Chung-Hyun CH Jeon Yoon Kyung YK Kim Yeon-Sook YS Cho Nam-Hyuk NH

Cell reports 20210920 1

Despite the worldwide effect of the coronavirus disease 2019 (COVID-19) pandemic, the underlying mechanisms of fatal viral pneumonia remain elusive. Here, we show that critical COVID-19 is associated with enhanced eosinophil-mediated inflammation when compared to non-critical cases. In addition, we confirm increased T helper (Th)2-biased adaptive immune responses, accompanying overt complement activation, in the critical group. Moreover, enhanced antibody responses and complement activation are ...[more]

PMID: 34587481

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Dataset Information

Enhanced eosinophil-mediated inflammation associated with antibody and complement-dependent pneumonic insults in critical COVID-19.

Publications

Enhanced eosinophil-mediated inflammation associated with antibody and complement-dependent pneumonic insults in critical COVID-19.

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