Fig. 3

IFNα-induced expression of ISG15 is impaired in latently HIV-infected U1 and OM10.1 cells. Cell lines were treated with increasing concentrations of exogenous IFNα for 24 h. Following stimulation, cells were fixed and permeabilized, after which intracellular ISG15 expression was measured by flow cytometry. Representative histogram and cumulative data of IFNα-induced ISG15 expression normalized to unstimulated controls is shown for a U937 and U1 cells (n = 6) and b HL60 and OM10.1 cells (n = 8). ^† p < 0.0001 by one-way ANOVA and p < 0.05 by pairwise Dunnett’s Test compared to unstimulated cells. *p < 0.001; **p < 0.05 by Two-way ANOVA with Bonferroni post-test for multiple comparisons