Fig. 4

PolyI:C increases cilia-driven flow and ciliary activity via Toll-like receptor 3 (TLR3) signaling. WT and TLR3-KO murine tracheal epithelia were incubated for 30 min with or without polyI:C in the culture medium, and then cilia-driven flow and ciliary beat frequency (CBF) were evaluated. a Representative beads trajectories of cilia-driven flow in WT culture (rainbow trace for 4.4 s). b and c Both the histogram (b) and bar chart (c) of cilia-driven flow demonstrated that polyI:C treatment significantly increased cilia-driven flow in WT culture (Ctrl, 6.96 ± 0.21 µm/s; polyI:C, 9.20 ± 0.23 µm/s; n = 150 beads in each condition). d Kymographs of ciliary beating in WT culture. e PolyI:C treatment significantly increased CFB in WT culture (Ctrl, 14.51 [12.80–16.21] Hz; polyI:C, 16.21 [12.80–19.62] Hz; n = 30 in each condition). f The amplitude of ciliary beating did not differ between the two conditions (Ctrl, 5.80 ± 0.38 µm; polyI:C, 5.72 ± 0.28 µm). g Representative beads trajectories of cilia-driven flow in TLR3-KO culture (rainbow trace for 4.4 s). h and i Both the histogram (h) and bar chart (i) of cilia-driven flow demonstrated that polyI:C treatment had no impact on cilia-driven flow in TLR-KO culture (Ctrl, 8.50 ± 0.34 µm/s; polyI:C, 8.99 ± 0.34 µm/s; n = 150 beads in each condition). j Kymographs of ciliary beating in TLR3-KO culture. k PolyI:C treatment did not affect CBF in TLR3-KO culture (Ctrl, 14.92 [11.95–16.21] Hz; polyI:C, 15.36 [10.45–17.92] Hz; n = 30 in each condition). l The amplitude of ciliary beating was not different between the conditions (Ctrl, 5.78 ± 0.25 µm; polyI:C, 5.76 ± 0.24 µm). *p < 0.01, **p < 0.05. Ctrl control, ns not significant. CBF data were presented as the median (range)