Potential value of circulating endothelial cells for the diagnosis and treatment of COVID-19

Zhang, Xuchang; Jiang, Man; Yang, Jianshe

The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been a formidable global challenge. As yet, there are very few drugs to treat this infection and no vaccine is currently available. We have gradually come to realize that coronavirus disease 2019 (COVID-19) is not a simple disease involving a single organ; rather, many vital organs and systems are affected. The endothelium is also a target of SARS-CoV-2. Damaged endothelial cells, which break away from organs and enter the blood to form circulating endothelial cells, were recently reported as putative biomarkers for COVID-19. Additionally, by modulating the expression level of sphingosine-1 phosphate via sphingosine kinase activation, endothelial cell proliferation and apoptosis can be controlled. Thus, it may be possible to obtain a sensitive and specific diagnosis of COVID-19 severity by assessing the absolute number and the viable/apoptotic ratio of circulating endothelial cells. Furthermore, a focus on the endothelium could help to develop a strategy for COVID-19 treatment from the perspective of endothelium protection and repair.