Journal: NAR Molecular Medicine

Article Title: Human pneumovirus induces IFN-dependent expression of the immune-responsive gene 1 and is inhibited by 4-octyl itaconate in human macrophages

doi: 10.1093/narmme/ugag017

Figure Lengend Snippet: TBK1 and NF-κB positively regulate IRG1 levels in HMPV-infected human macrophages. MDMs were incubated with 5 or 10 μM of the TBK1 inhibitor BX795 for 30 min before infection with HMPV for 24 h. ( A ) IRG1 and IFN-β mRNA levels ( n ≥ 3) were analysed by qRT-PCR (left panels), while in panel ( B ) IRG1 and GAPDH protein levels were determined by immunoblotting, quantified, and presented with SD relative to uninfected cells treated with DMSO ( n = 2; right panel). (C–K) MDMs were transfected with siRNAs targeting the NF-κB subunit RELA (C–E), IRF1 (F–H), RIPK3 (I–K), or control siRNA (siNTC) before infection with HMPV for 6, 9, or 24 h and analysis of IRG1 mRNA levels by qRT-PCR or IRG1, RelA/p65, IRF1, RIPK3, or GAPDH protein levels by immunoblotting. IRG1 mRNA levels were assessed relative to siNTC-transfected, uninfected MDMs for all experiments. ( C, E ) IRG1 mRNA after 6 h ( n = 3) or 24 h HMPV ( n = 3). ( D ) Protein levels of IRG1, RelA/p65, and GAPDH ( n = 3) after 9 h HMPV. ( F, H ) IRG1 mRNA after 6 h ( n = 4) or 24 h of infection ( n = 3). ( G ) Protein levels of IRG1, IRF1, and GAPDH ( n = 3) after 9 h HMPV. ( I, K ) IRG1 mRNA after 6 h ( n = 3) or 24 h of infection ( n = 3). ( J ) Protein levels of IRG1, IRF1, and GAPDH ( n = 3) after 9 h HMPV. ( L ) MDMs were incubated with 100 nM of the RIPK3 inhibitor GSK 872 for 1 h before infection with HMPV for 24 h. IRG1 mRNA levels were normalized relative to uninfected cells treated with DMSO ( n = 2). Single comparison between control (NTC) siRNA and target-siRNA conditions were calculated using paired t -test with Tukey post-hoc test. * P < .05, ** P < .01, *** P < .001, **** P < .0001; ns = non-significant. See also

Article Snippet: Inhibition with S-Ruxolitinib (Merck) or GSK 872 (GlaxoSmithKline) was performed 1 h before infection with HMPV, whereas BMS-303141 (MedChemExpress) was preincubated for 2 h. The IFNAR neutralizing antibody (nIFNAR, clone MMHAR-2) was purchased from PBL; 5 or 10 μg/ml were incubated for 30 min before infection with HMPV.

Techniques: Infection, Incubation, Quantitative RT-PCR, Western Blot, Transfection, Control, Comparison