COVID-19 patients upregulate toll-like receptor 4-mediated inflammatory signaling that mimics bacterial sepsis

Sohn, K. M.; Lee, S.-G.; Kim, H. J.; Cheon, S.; Jeong, H.; Lee, J.; Kim, I. S.; Silwal, P.; Kim, Y. J.; Park, C.; Kim, Y.-S.; Jo, E.-K.

doi:10.1101/2020.07.17.207878

bioRxiv · 10.1101/2020.07.17.207878

COVID-19 patients upregulate toll-like receptor 4-mediated inflammatory signaling that mimics bacterial sepsis

Sohn, K. M.·Lee, S.-G.·Kim, H. J.·Cheon, S.·Jeong, H.·Lee, J.·Kim, I. S.·Silwal, P.·Kim, Y. J.·Park, C.·Kim, Y.-S.·Jo, E.-K.

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Abstract

Observational studies of the ongoing coronavirus disease 2019 (COVID-19) outbreak suggest that a cytokine storm is involved in the pathogenesis of severe illness. However, the molecular mechanisms underlying the altered pathological inflammation in COVID-19 are largely unknown. We report here that toll-like receptor (TLR) 4-mediated inflammatory signaling molecules are upregulated in peripheral blood mononuclear cells (PBMCs) from COVID-19 patients, compared with healthy controls. Among the most highly increased inflammatory mediators in severe/critically ill patients, S100A9, an alarmin and TLR4 ligand, was found as a noteworthy biomarker, because it inversely correlated with the serum albumin levels. These data support a link between TLR4 signaling and pathological inflammation during COVID-19 and contribute to develop therapeutic approaches through targeting TLR4-mediated inflammation.

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Sohn, K. M., Lee, S.-G., Kim, H. J., Cheon, S., Jeong, H., Lee, J., Kim, I. S., Silwal, P., Kim, Y. J., Park, C., Kim, Y.-S., Jo, E.-K.. 2020-07-17. COVID-19 patients upregulate toll-like receptor 4-mediated inflammatory signaling that mimics bacterial sepsis. https://doi.org/10.1101/2020.07.17.207878

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