Figure 1. IFIT1 Depletion in Human Macrophages Leads to an Enhanced LPS-Induced TNF-α Response.
(A) Schematic for the TNF-α reporter assay used in a genome-wide screen of the LPS response in human THP1 cells (Sun et al., 2017). (B) Screen hit distribution showing TLR4 as a validating positive regulator hit and identification of IFIT1 as a negative regulator of LPS-induced TNF-α expression. (C-E) Primary human macrophages transfected with control or IFIT1 siRNA were stimulated with 100 ng/mL LPS for the indicated times, IFIT1 (C) or TNF (D) mRNA was measured by qPCR, and secreted TNF-α (E) was measured by ELISA. Data are representative of four independent experiments and expressed as mean ± SD; *p < 0.05, **p < 0.01, ***p < 0.001 (two-way ANOVA followed by Sidak’s multiple comparison test). See also Figure S1.