TNFRSF11B and pulmonary arterial hypertension: Furthermore, we propose that inhibition of OPG, e.g. via antibody blockade, will prevent this signalling and subsequent alteration in pro-PAH gene expression leading to a reversal of pulmonary vascular remodelling, normalisation of pulmonary vascular resistance and inhibition of PAH via alteration in the proliferation, migration and apoptosis of pulmonary vascular cells (Fig. 5j).