The Inflammatory Factors Associated with Disease Severity to Predict COVID-19 Progression

Coronavirus disease 2019 ( COVID- 19) is associated with immune dysregulation and cytokine storm. Exploring the immuneinflammatory characteristics of COVID-19 patients is essential to reveal pathogenesis and predict progression. In this study, COVID-19 patients showed decreased CD3(+), CD4(+), and CD8+ T cells but increased neutrophils in circulation, exhibiting upregulated neutrophil-to-lymphocyte and neutrophil-to-CD8+ T cell ratio. IL-6, TNF-alpha, IL-1 beta, IL-18, IL-12/IL-23p40, IL- 10, Tim-3, IL-8, neutrophil extracellular trap-related proteinase 3, and S100A8/A9 were elevated, whereas IFN-gamma and C-type lectin domain family 9 member A (clec9A) were decreased in COVID-19 patients compared with healthy controls. When compared with influenza patients, the expressions of TNF-alpha, IL-18, IL-12/IL- 23p40, IL-8, S100A8/ A9 and Tim-3 were significantly increased in critical COVID-19 patients, and carcinoembryonic Ag, IL-8, and S100A8/A9 could serve as clinically available hematologic indexes for identifying COVID-19 from influenza. Moreover, IL-6, IL-8, IL-1 beta, TNF-alpha, proteinase 3, and S100A8/A9 were increased in bronchoalveolar lavage fluid of severe/critical patients compared with moderate patients, despite decreased CD4(+) T cells, CD8(+) T cells, B cells, and NK cells. Interestingly, bronchoalveolar IL-6, carcinoembryonic Ag, IL-8, S100A8/A9, and proteinase 3 were found to be predictive of COVID-19 severity and may serve as potential biomarkers for predicting COVID-19 progression and potential targets in therapeutic intervention of COVID-19.

Automated summary

COVID-19 is associated with immune dysregulation and cytokine storm, leading to altered levels of various immune cells and cytokines in the body. Some specific factors could potentially be used as biomarkers for predicting disease severity and progression.