Although the mechanism by which the virus promotes neutrophil development in COVID-19 is still poorly understood, McElvaney et al.60 found that the levels of pyruvate kinase M2 (PKM2), a regulator of glycolysis61 and coactivator of hypoxia-inducible factor-1α,62 as well as phosphorylated PKM2 were higher in the neutrophils of COVID-19 patients in the ICU than in those of non-ICU COVID-19 patients. Here, PKM is linked to COVID-19.