Fig. 3: USP18 deficient mice are susceptible to RNA virus infection.
a Immunoblot analysis of SeV in lysates of Usp18+/+ and Usp18−/− MEFs infected with SeV for 0–12 h. b Immunoblot analysis of SeV in lysates of 293T cells transfected with Myc-USP18 in different dosages followed by infection with SeV for 8 h. c Immunoblot analysis of SeV in lysates of 293T cells transfected with EGFP-N1 plasmid in different dosages followed by infection with SeV for 8 h. d ELISA analysis of IFN-β level in serum of Usp18+/+ and Usp18−/− mice (five per group) infected for 12 h by intraperitoneal injection of VSV (2 × 107 PFU per mouse). Representative data were collected and expressed as mean ± SD from at least three independent experiments. Two-tailed Student’s t test was performed, *p = 0.0114. e Plaque assay of VSV titers in the brain, spleen, liver, and lungs of Usp18+/+ and Usp18−/− mice (four per group) infected for 36 h by intraperitoneal injection of VSV (2 × 107 PFU per mouse). Representative data were collected and expressed as mean ± SD from at least three independent experiments. Two-tailed Student’s t test was performed, *p = 0.0464, *p = 0.0178, *p = 0.0468, *p = 0.0428 in sequence. f Immunoblot analysis of VSV-GFP in the spleen, liver, and lungs of Usp18+/+ and Usp18−/− mice (four per group) as in e. g Survival (Kaplan–Meier curves) of Usp18+/+ and Usp18−/− mice (eight per group) injected intraperitoneally with VSV (1 × 108 PFU per mouse), with log rank test [Mantel-Cox], with ****p < 0.0001. h Hematoxylin-and-eosin-stained images of lung sections from mice as in e. Scale bars, 50 µm.
