SCAF11 and COVID-19: Thus, to determine if CASP11 and GSDMD modulate neutrophil functions during SARS–CoV-2 infection, WT, Casp11−/−, and Gsdmd−/− neutrophils were treated with phorbol myristate acetate (PMA) (Fig. 4 A and B) or culture supernatants from WT epithelial cells infected with SARS–CoV-2 to simulate the virus-induced inflammatory milieu (SI Appendix, Fig. 6).