The anti-inflammatory population was unconventional in that it had an upregulation of classic pro-inflammatory cytokines IL-1A and IL-1B but also an upregulation of genes associated with a unique and novel monocytic cluster found in human COVID-19 patients such as AREG, EREG, IL10, IL18 and BCL6 (59, 72). Here, AREG is linked to COVID-19.