CXCL8 and acute respiratory distress syndrome: Calfee and colleagues reported that a parsimonious set of three biologic markers identified patients with higher mortality versus lower mortality for classical ARDS prior to COVID-19 (interleukin-8, Protein C, and bicarbonate), and this approach worked very well even in a re-analysis of the START-2 trial 60 patient trial of MSCs versus placebo [134].