TGFβ1 generates a pro-fibrotic proteome in human lung parenchyma that is sensitive to pharmacological intervention.

Background: & Aim: Novel treatments for idiopathic pulmonary fibrosis (IPF) are needed urgently. A better understanding of the molecular pathways activated by TGFβ1 in human lung tissue may facilitate the development of more effective anti-fibrotic medications. This study utilized proteomic analysis to test the hypothesis that TGFβ1 induces pro-fibrotic effects on human lung parenchyma proteome, and to evaluate the viability of this model for testing novel therapeutic targets.

Methods: Non-fibrotic human lung parenchymal tissue from 11 patients was cultured for 7 days in serum-free (SF) media supplemented with TGFβ1 (10 ng/mL) or vehicle control, and the putative antifibrotic KCa3.1 ion channel blocker senicapoc or vehicle control. The tissue was homogenized, digested for bottom-up proteomics, and analysed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Principal component analysis, differential expression analysis, pathway analysis, and drug repurposing analysis were performed.

Results: TGFβ1 stimulation for 7 days induced a strong fibrotic protein response relevant to IPF pathology. A total of 2,391 proteins were quantified, 306 upregulated and 285 downregulated (FDR-adjusted p-value<0.05). Of these, 118 were upregulated and 28 downregulated at log2(FC)>0.58. These changes were attenuated by senicapoc (100 nM). Drug repurposing analysis identified 265 drugs predicted to inhibit the effects of TGFβ1 in this model. These included clotrimazole, a KCa3.1 blocker, and nintedanib, a drug licenced for the treatment of IPF, providing validation of this approach.

Conclusions: A pro-fibrotic proteome is induced in human lung parenchyma exposed to TGFβ1, sensitive to pharmacological intervention. This approach has the potential to enhance therapeutic drug screening for IPF treatment.