JAG1 and pulmonary arterial hypertension: 146), or NOTCH3 ligand interactions (Ref. 66) have been successfully developed. These antibodies have been shown to provide anti-cancer activity and reverse pathology associated with IPF and PAH using in vitro and in vivo pre-clinical models of disease (Refs 66, 144). While blocking NOTCH ligands maybe less specific than directly targeting the receptor, this approach has proved successful in a pre-clinical murine asthma model, whereby blocking antibodies targeting the JAG1 and JAG2 ligands reversed OVA-induced GCMH (Ref. 147).