(E, F) GSDMD-/- THP-1 cells rescued with wild-type or linker substituted GSDMD were infected with SARS-CoV-2 at an MOI of 1 for 1h, followed by washing away extracellular viruses and further culture for 3 h. Otherwise, cells were stimulated with 10 μM nigericin for 30 min following pretreatment with 1 μg/ml LPS for 3 h. Supernatants were subjected to an ELISA assay to determine IL-1β levels (E). Otherwise, cell viability in cell pellets was examined using a cell viability assay through checking ATP levels inside cells (F). For E, F, Student's t-test was used and data were shown as means±SD of three technical replicates. **, P<0.01; ***, P<0.001; NS, non-significant. Results were repeated for three times with similar results. 