Mitosis does not elicit an innate immune response. (A) Western blot analysis of THP-1 cells synchronized at G2, M, or G1-asynchronous to determine p-TBK1 levels. Cells were synchronized at G2 using RO-3306. (B) Western blot analysis of THP-1 cells stimulated with LPS or poly I:C for 1 h and 8 h, respectively. Blots were probed for p-TBK1 and NAP1. (C–D) Relative mRNA expression of cytokines normalized to β-actin in THP-1 cells when stimulated with LPS (C) for 1 h or poly I:C (D) for 8 h. Error bars indicate ±SD; n = 3 independent experiments. (E) Relative mRNA expression of cytokines during different cell cycle stages normalized to β-actin in THP-1 cells. Error bars indicate ±SD; n = 3 independent experiments. Cells were synchronized at G2 using RO-3306. (F) Western blot analysis of p-IRF3 and p-IKKe in THP-1 cells synchronized at G2, M, or G1-asynchronous or stimulated with LPS or poly I:C for 1 h and 8 h, respectively. Cells were synchronized at G2 using RO-3306.Student’s t test (C and D) or one way ANOVA (E) was performed for all statistical analysis. * P < .05, ** P < .01, *** P < .001, ns = not significant. Source data are available for this figure: SourceData FS2.