Increased intercellular adhesion molecule (ICAM1) was observed in HPAH iMono compared to control iMono (Fig. 6F), consistent with studies indicating that Bmpr2 knockout monocyte lineage mice (Bmpr2KO) show elevated soluble ICAM1 in the circulation and in lung tissue following Sugen/hypoxia-induced pulmonary hypertension [6]. This evidence concerns the gene BMPR2 and pulmonary arterial hypertension.