TGFB1 and fibrosis: In the profibrotic environment, several progenitor cell types, such as resident fibroblasts, epithelial cells, and endothelial cells, can be activated and differentiate into myofibroblasts.[1c] To examine whether FNPs could suppress the profibrotic effect of TGF‐β1, different resident mesenchymal cells from different organs, including lung fibroblasts, CFBs, and hepatic stellate cells, were used to establish in vitro fibrosis models.