Although high pulsatile flow has been found to increase TGFβ signaling (Scott et al., 2013) and altered TGFβ superfamily signaling is one of the hallmarks of familial and idiopathic PAH (Eickelberg and Morty, 2007; Aschner and Downey, 2016), direct mechanical activation of TGFβ has not yet been well studied in pulmonary vascular cells. Here, TGFB1 is linked to pulmonary arterial hypertension.