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bioRxiv · 10.1101/2021.09.29.462202

A virus-specific monocyte inflammatory phenotype is induced by SARS-CoV2 at the immune-epithelial interface

Abstract

Infection by SARS-CoV2 provokes a potentially fatal pneumonia with multiorgan failure, and high systemic inflammation. To gain mechanistic insight and ferret out the root of this immune dysregulation, we modeled by in vitro co-culture the interactions between infected epithelial cells and immunocytes. A strong response was induced in monocytes and B cells, with a SARS-CoV2-specific inflammatory gene cluster distinct from that seen in influenza-A or Ebola virus-infected co-cultures, and which reproduced deviations reported in blood or lung myeloid cells from COVID-19 patients. A substantial fraction of the effect could be reproduced after individual transfection of several SARS-CoV2 proteins (Spike and some non-structural proteins), mediated by soluble factors, but not via transcriptional induction. This response was greatly muted in monocytes from healthy children, perhaps a clue to the age-dependency of COVID-19. These results suggest that the inflammatory malfunction in COVID-19 is rooted in the earliest perturbations that SARS-CoV2 induces in epithelia.

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BibTeXRIS

Leon, J., Michelson, D. A., Olejnik, J., Chowdhary, K., Oh, H. S., Hume, A. J., Galvan-Pena, S., Zhu, Y., Chen, F., Vijaykumar, B., Yang, L., Crestani, E., Yonker, L. M., Knipe, D. M., Muhlberger, E., Benoist, C.. 2021-09-29. A virus-specific monocyte inflammatory phenotype is induced by SARS-CoV2 at the immune-epithelial interface. https://doi.org/10.1101/2021.09.29.462202

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