TGFB1 and pulmonary arterial hypertension: To validate the findings derived from in silico modeling in a reliable, controllable, and cell-based model, BMP- and TGF-β-responsive reporter activities were detected in HEK293T cells, which are widely employed for mechanistic studies of TGF-β and BMP signaling in PAH due to their well-defined genotype and high transfection efficiency [6,10,58,59,60,61,62].