Figure 1Reanalysis of published single-cell sequencing data (GSE163668) of SARS-CoV-2 patient PBMCs. t-Distributed Stochastic Neighbor Embedding (tSNE)-based visualization of single-cells containing PBMCs from healthy donors, SARS-CoV-2 infected mild/moderate and severe patients was shown on the left panel and cluster annotations were shown on the right (A). Percentage of non-classical monocytes in each sample group were calculated (B). each dot represents an individual. Brown-Forsythe and Welch ANOVA test was used and data were shown as means±SD. *, P<0.05; **, P<0.01; NS, non-significant. Data information: Brown-Forsythe and Welch ANOVA test was used and data were shown as means±SD. Relative average expression levels of IL1B and NLRP3 in non-classical monocytes of each group were calculated (C). n=20 for healthy donor, n=9 for mild/moderate, n=7 for severe. each dot represents an individual. Brown-Forsythe and Welch ANOVA test was used and data were shown as means±SD. *, P<0.05; **, P<0.01; NS, non-significant. Data information: Brown-Forsythe and Welch ANOVA test was used and data were shown as means±SD. (D-F) CD14+ monocytes sorted from healthy PBMCs were infected with SARS-CoV-2 viruses at an MOI of 1 for 1 h, followed by washing away extracellular viruses and further culture to meet the indicated infection time. Supernatants were collected and subjected to RT-PCR analysis of viral RNAs (D) and ELISA assay of IL-1β (E). The percentage of cells undergoing cell death was calculated through checking released LDH in the supernatants (F). For D-F, Student's t-test was used and data were shown as means±SD of three technical replicates. ***, P<0.001; results were repeated for three times with similar results. Data information: Student's t-test was used and data were shown as means±SD of three technical replicates. *, P<0.05; **, P<0.01; ***, P<0.001; NS, non-significant. results were repeated for three times with similar results. (G) Sorted human monocytes were incubated with control medium or SARS-CoV-2 viruses at an MOI of 1 for 1 h, followed by washing away extracellular viruses and further culture for 1 h. Cells were fixed and stained with the indicated antibodies. Otherwise, monocytes were challenged with 1 μg/ml LPS for 3 h and 10 μM nigericin for 30 min, followed by fixing and staining with the indicated antibodies. Treatment with medium from uninfected Vero cells served as a control. Scale bar: 5 μm. Data information: results were repeated for three times with similar results. Supernatants from control or SARS-CoV-2 infected CD14+ monocytes with or without LPS and nigericin stimulation were collected and subjected to an ELISA assay for IL-1β levels (H). Student's t-test was used and data were shown as means±SD of three technical replicates. *, P<0.05; **, P<0.01; ***, P<0.001; NS, non-significant. Results were repeated for three times with similar results. Data information: , Student's t-test was used and data were shown as means±SD of three technical replicates. *, P<0.05; **, P<0.01; ***, P<0.001; NS, non-significant. results were repeated for three times with similar results. Cell viability in cell pellets were examined using a cell viability assay through checking ATP levels inside cells (I). The percentage of cells undergoing pyroptosis was calculated through checking released LDH in the supernatants (J). Student's t-test was used and data were shown as means±SD of three technical replicates. *, P<0.05; **, P<0.01; ***, P<0.001; NS, non-significant. Results were repeated for three times with similar results. Data information: Student's t-test was used and data were shown as means±SD of three technical replicates. *, P<0.05; **, P<0.01; ***, P<0.001; NS, non-significant. results were repeated for three times with similar results.