FIG 2.

Effect of glutamine deprivation on virus replication and interferon induction. (A) Virus produced after in vitro NSV infection at MOIs of 1 and 10 of BHK cells in either complete medium [Gln(+)], glutamine-deficient medium [Gln(−)], or complete medium with the glutamine antagonist DON (100 μM) or ACI (100 μM). BHK cells were glutamine and serum starved for 24 h before infection with NSV. Supernatant fluids were collected 24 h after infection and assayed for plaque formation on BHK cells. (B) Viral titers from the brains and spinal cords of PBS-treated (NSV) and DON-treated (NSV + DON) (0.6 mg/kg for brain and 0.3 mg/kg for spinal cord) mice. Error bars represent standard errors of the geometric mean titers from three biological replicates (A) or three mice (B). The dotted line represents the limit of detection of the plaque assay. Data are representative of results from at least two independent experiments (B). (C) Levels of IFN-α and IFN-β in the brains of PBS-treated (NSV) and DON-treated (NSV + DON) (0.3 mg/kg) mice as determined by EIAs. Data represent the means ± standard errors of the means of data for 3 mice. Gray shading or underlining designates the drug treatment period. *, P < 0.05; ***, P < 0.001 (as determined by one-way ANOVA with Dunnett's posttest [A] or two-way ANOVA with a Bonferroni posttest [B and C]).