FIGURE 2.

Poly(I:C) but not NA activates TGFβ in human bronchial epithelial cells. A, iHBECs were co-cultured with TMLCs and stimulated with poly(I:C) (0, 10, 15, or 20 μg/ml) without inhibitors (black bars) and with either the pan-TGFβ-neutralizing antibody 1D11 (10 μg/ml; gray bars) or the αvβ6-blocking antibody 6.3G9 (15 μg/ml; white bars). Experiments were performed in duplicate and repeated three times. The mean fold change in total luciferase units compared with control (mock- infected without inhibitors) of the independent experiments was determined. Data are expressed as mean ± S.E. p < 0.0001 between treatment groups and stimulation versus control. B, iHBECs were transiently transfected with the TGFβ-sensitive promoter reporter construct CAGA₁₂-MLP-Luc and Renilla luciferase pRL-SV40 prior to stimulation with 20 μg/ml poly(I:C) for 6 h. Experiments were performed in duplicate and repeated three times. The mean fold change in the F:R ratio versus control (mock-infected) of the independent experiments was determined. Data are expressed as mean ± S.E. **, p < 0.01. C, iHBECs were co-cultured with TMLCs and stimulated with increasing concentrations of recombinant NA (0, 0.1, 1, 10, and 100 units) with (white bars) and without (black bars) the pan-TGFβ-neutralizing antibody 1D11 (10 μg/ml). Experiments were performed in duplicate and repeated three times. The mean fold change in total luciferase units compared with control (mock-infected without inhibitors) of the independent experiments was determined. Data are expressed as mean ± S.E. p < 0.0001 between treatment groups; no effect of stimulation versus control. D, iHBECs were transiently transfected with the TGFβ-sensitive promoter reporter construct CAGA₁₂-MLP-Luc, and Renilla luciferase pRL-SV40 prior to stimulation with increasing concentrations of NA (0–100 units) for 6 h. Experiments were performed in duplicate and repeated three times. The mean fold change in the F:R ratio versus control (mock-infected) of the independent experiments was determined. Data are expressed as mean ± S.E.