TGFB1 and pulmonary arterial hypertension: Upregulation of TGF-β has also been reported in several animal models of PAH [12], [13], and decreased TGF-β signaling related to dominant negative TGF-β type II receptor (TGF-βRII) overexpression [12], [14] or anti-TGF-β antibody [15] protects against PAH.