CXCL8 and COVID-19: Similar approaches to identifying soluble mortality predictors of COVID-19 have involved the use of classical flow-cytometry bead arrays, and extended panels investigating multiple pro-and anti-inflammatory cytokines (e.g., Il-1β, IL-2, IL-4, IL-6, MCP-1, IP-10, IL-8, IL-12, IFN-γ, TNF-α) confirmed previously reported findings [117,118].