Among inflammatory cytokines associated with SIV-PAH, bronchoalveolar lavage fluid (BALF) TGF-β (Fig. 3a, P = 0.02) and plasma MIP-1α (Fig. 3b, P = 0.02) and TNF-α (Fig. 3c, P = 0.049) levels are significantly higher in SIV-PAH+ animals compared with SIV-PAH− controls. Here, TGFB1 is linked to pulmonary arterial hypertension.