Fig. S2.

MHV nsp15 mutant viruses induce type I IFN in macrophages. (A) B6 BMDMs were infected with WT or N15m1 MHV at an MOI of 0.1. At 12 hpi, infected cells were fixed with 4% formaldehyde and stained with Hoechst 33342 (nucleus; blue), antinucleocapsid (N; red), and anti-ISG54 (green). Immunofluorescence was detected by confocal microscopy. (Magnification, 200×.) (B) ifih1^−/− BMDMs were infected at an MOI of 0.1. IFN-α11 mRNA levels were determined by quantitative PCR. Values were relative to β-actin. Data are representative of two to three independent experiments and error bars represent the mean ± SD.