ITGAM and bacterial infectious disease: The integrin receptor CD11b has been upregulated on neutrophils and monocytes upon exposure to viral and bacterial infections.22 It is suggested to be a useful marker of neonatal sepsis.23 A recent study of COVID-19 patients demonstrated a decrease in granulocyte CD11b expression.6 Blocking CD11b has been proposed to have a beneficial effect on sepsis outcome.24