The oxysterol, 25-HC, reduced the titer of MNV. RAW264.7 were infected with MNV at a MOI of approximately (A) 0.05 TCID50/cell or (B) 5 TCID50/cell and immediately treated with 25-HC (6.6 µM), nystatin (50 µM) or ethanol-only control. At regular intervals, replicate wells were harvested, supernatant clarified by centrifugation and virus titer determined by TCID50 assay. Data show mean virus titer (n = 3 ± SEM, * = p < 0.05, ** = p < 0.01, *** = p < 0.001). (C) RAW264.7 cells were infected with MNV and immediately treated with 25-HC (6.6 µM), nystatin (50 µM) or ethanol-only control. At 12 h post-infection, the expression of MNV NS1/2 protein was detected by indirect immunofluorescence and the number of virus positive cells was quantified using an IncuCyte ZOOM FLR. Data show the mean number of virus-infected cells per well and statistical analysis compared to ethanol-only control (n = 3 ± SEM, *** = p < 0.001).