Fig. 2

INF-γ and PFD inhibit the proliferation of NHLFs and IPF fibroblasts in response to TGF-β1 and PDGF-BB. NHLFs and IPF fibroblasts were stimulated with either TGF-β1 2.5 ng/ml (a & b) or PDGF-BB 20 ng/ml (c-f) in the presence of INF-γ [10–40 ng/mL], PFD [300–500 μg/mL] or a combination of IFN-γ/PFD for 1, 3 and 5 days. Cell Titer 96® Non-Radioactive Cell Proliferation Assay (a-d) and cell counting using trypan blue staining and an automated Cellometer (e & f) revealed the proliferative response to both TGF-β1 and PDGF-BB when compared with proliferation of the control, and both IFN-γ and PFD alone inhibited TGF-β1- and PDGF-BB-induced proliferation in both NHLFs and IPF fibroblasts. The combination of both IFN-γ and PFD treatment restrained cell proliferation to control levels. Data are presented as the means ± SEMs of 3 independent experiments, with each experiment run in duplicate. ^**P < 0.05 vs. TGF-β1 and ^## P < 0.05 vs. TGF-β1+ vehicle [DMSO]