Fig 3. BRD4 inhibition exerts broad-spectrum antiviral activity.

(a) Viral titer was assessed with TCID₅₀ assays in PK15 cells (Control) infected with PRV-QXX (MOI = 0.1 and 1) and treated with DMSO, JQ-1 (1 μM), OTX-015 (10 μM) and I-BET 151 (10 μM) for 24 h. (b) Viral titer was assessed with TCID₅₀ assays in A549 cells (Control) infected with HSV1-F (MOI = 1 and 10) and treated as in a. (c) Viral titer was assessed with TCID₅₀ assays in Vero cells (Control) infected with ECTV (MOI = 1 and 10) and treated as in a. (d) Viral titer was assessed with TCID₅₀ assays in PK15 cells (Control) infected with VSV-GFP (MOI = 0.001 and 0.01) and treated as in a. (e) Viral titer was assessed with TCID₅₀ assays in MARC-145 cells (Control) infected with PRRSV-BJ4 (MOI = 1 and 10) and treated as in a. (f and g) Viral titer was assessed with TCID₅₀ assays in Scramble, shBRD4-1 and shBRD4-2 PK15 cells infected with PRV-QXX (f, MOI = 0.1 and 1) and VSV-GFP (g, MOI = 0.001 and 0.01) for 24 h. All data are shown as mean ± SD based on three independent experiments. ** P < 0.01, *** P < 0.001 determined by two-tailed Student’s t-test.