FIG 2.

Infection with 1.5 and 150 HA U/ml of SeV results in distinct profiles of IFN-α subtype induction. U937 cells were infected with either 1.5 or 150 HA U/ml of SeV for 4, 8, 16, 24, and 48 p.i. RNA was harvested at each time point, and IFN-α and IFN-β subtype RNA was measured via qRT-PCR. (A) IFN-β and IFN-α subtypes in cells infected with 1.5 HA U/ml. (B) IFN-β and IFN-α subtypes in cells infected with 150 HA U/ml. The data are from 3 biological replicates performed in duplicate. Statistics were performed using one-way ANOVA with Bonferroni posttest analysis. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001. qRT-PCR data are shown as the percent relative expression of HPRT. (C) U937 cells were infected with either live or inactivated SeV (150 HA U/ml) for 24 h. The supernatants were harvested and then used to pretreat fresh U937 cells prior to EMCV infection. After 72 h, cell viability was measured via MTT assay, and the ability of the supernatants to restrict EMCV-induced CPE was analyzed. The error bars indicate the standard error of the mean.