Idiopathic pulmonary fibrosis (IPF) has a detrimental prognosis despite antifibrotic
therapies to which individual responses vary. IPF pathology is associated with oxidative stress,
inflammation and increased activation of
SRC family kinases (SFK). This pilot study evaluates individual responses to
pirfenidone,
nintedanib and SFK inhibitor
saracatinib, markers of redox homeostasis,
fibrosis and
inflammation, in IPF-derived human bronchial epithelial (HBE) cells. Differentiated HBE cells from patients with and without IPF were analyzed for potential alterations in redox and profibrotic genes and pro-inflammatory
cytokine secretion. Additionally, the effects of
pirfenidone,
nintedanib and
saracatinib on these markers were determined. HBE cells were differentiated into a bronchial epithelium containing ciliated epithelial, basal, goblet and club cells. NOX4 expression was increased in IPF-derived HBE cells but differed on an individual level. In patients with higher NOX4 expression,
pirfenidone induced
antioxidant gene expression. All drugs significantly decreased NOX4 expression.
IL-6 (p = 0.09) and
IL-8 secretion (p = 0.014) were increased in IPF-derived HBE cells and significantly reduced by
saracatinib. Finally,
saracatinib significantly decreased TGF-β gene expression. Our results indicate that treatment responsiveness varies between IPF patients in relation to their oxidative and inflammatory status. Interestingly,
saracatinib tends to be more effective in IPF than standard antifibrotic drugs.