PDGF receptor expression and PDGF-AA mediated recruitment of NHLF and IPF fibroblasts. (A) PDGFRα, PDGFRβ, and FGFR1 expression in fibroblasts with GAPDH as loading control. PDGFRα expression was markedly reduced in all IPF donors (n = 5) studied compared to the NHLF donors (n = 4). The expression of PDGFRβ expression was reduced in IPF fibroblasts and exhibited donor to donor variability. FGFR1 expression was variable across all donors irrespective of phenotype. (B) IPF fibroblasts showed significantly impaired migratory response to PDGF-AA whereas no difference was seen under baseline conditions. There was no difference in bFGF-mediated migration between phenotypes with both NHLFs and IPF fibroblasts showing significant induction of migration. (C) Similarly, significantly higher induction of proliferation was seen in NHLFs in response to PDGF-AA with no difference in bFGF induced proliferation compared to IPF fibroblasts. A concentration of 2× ED50 was used in all assays for each cytokine. *P <0.05.