Fig 2: cGAS mediates the autoimmunity in TLR7-driven systemic lupus erythematosus.a Plasma cGAMP concentrations of healthy donors (n = 20), SLE patients (n = 20), RA patients (n = 20) and DM patients (n = 20). b Correlation analysis between plasma cGAMP levels and TLR7 expression of SLE patients (n = 44). c Analysis of cGAMP in bone marrow cells at the indicated times after R837 treatment (n = 6 independent biological replicates). d, e Plasma cGAMP levels of IMQ-induced mice at indicated time points (n = 5 independent biological replicates). Representative images of spleens of WT and Cgas–/– mice treated with IMQ for 4 weeks (f), and the ratio of spleen to body weight was calculated (g) (n = 8 independent biological replicates). ELISA detection of serum anti-nuclear antibodies (h), anti-dsDNA antibodies (i) and IFN-α concentrations (j) of WT and Cgas–/– BALB/c mice treated with IMQ for 4 weeks (n = 8 independent biological replicates). k Immunofluorescent staining of IgG (purple) and IgM (green) in kidneys from WT and Cgas–/– mice treated with IMQ for 4 weeks. Representative images are shown. Scale bar, 20 μm. The quantitative analysis was performed (n = 10 independent biological replicates). l HE-stained section of kidney from WT and Cgas–/– mice treated with IMQ for 4 weeks. Scale bar, 200 μm (top) and 50 μm (bottom). Representative images are shown. Percentage of the quantitative inflammatory cell infiltration scores (n = 5 per group). Bone marrow cells (m, 6 independent biological replicates) or pDCs (n, 3 independent biological replicates) from WT and Cgas–/– mice were treated with R837 and the IFN-α concentrations were measured. o Analysis of cGAMP in bone marrow cells pretreated as indicated and then treated with R837 (n = 3 independent biological replicates). NT, non-treated (e, m, n, o). Statistical significance was determined using one-way ANOVA with Tukey’s test (a, c–e, g–j); two-tailed student’s unpaired t-test (k); two-way ANOVA with Tukey’s test (m–o). Data are presented as the means ± SEM (c–e, g–k, m–o). P values are shown with figures. Source data are provided as a Source Data file.