Figure 4.

S100a4 promotes activation of lung fibroblasts. (A) Primary lung fibroblasts were treated with various concentrations of recombinant S100a4 (0–3 µg/ml) for 24 h, and expression of α-SMA was assessed by qRT-PCR. Results are mean ± SD of duplicate samples from one experiment. (B) Cells were treated with 2 µg/ml recombinant S100a4 or with recombinant S100a4 in the presence of a S100a4 neutralizing antibody for 24 and 48 h, respectively. Cells were harvested and analyzed for expression of α-SMA and collagen I by western blot. S100a4 neutralization eliminated activation of lung fibroblasts. Results are representative of three independent experiments with similar results.