TSLP and idiopathic pulmonary fibrosis: Based on our study finding of elevated systemic and lung compartment levels of TSLP in patients with IPF compared to controls and a finding of a significant decrease of TSLP lung compartment levels after 12 months of antifibrotic therapy observed in stable patients with IPF, but not in progressors, we speculate, that targeting TSLP functional signaling axis in a fibrotic lung disease may have a therapeutic potential in fibroproliferative lung diseases, such as IPF.