Severe COVID-19 is marked by a dysregulated myeloid cell compartment

SARS-CoV-2 infection induces profound alterations of the myeloid compartment with activation of emergency myelopoiesis leading to accumulation of immature and dysfunctional neutrophils in the blood and lung of severe COVID-19 patients. Calprotectin level, biomarker for neutrophils and monocytes activation, positively correlates with COVID-19 disease severity.