When focusing on the molecules reported in Fig. 3C, we detected a wide set of interactions between monocyte-derived (but also CD4+ T cell-derived) chemokines (i.e., CCL3, CXCL1, CXCL2, and CXCL8) binding CCR3 and CXCR1/2 on neutrophil subsets, particularly evident in patients with severe COVID-19 (Fig. 3G) (38). Here, CXCL1 is linked to COVID-19.