ACKR1 and COVID-19: Furthermore, an upregulation of IL1R1 (interleukin 1 receptor type 1), SOCS2 (suppressor of cytokine signaling 2) and ACKR1 [atypical chemokine receptor 1 (Duffy blood group)] implies a dysregulated cytokine/chemokine response, which may be the correlate of the cytokine storm observed in severe COVID-19 (28).