ADAMTS1 and pulmonary arterial hypertension: Indeed, ADAMTS 1, 4, and 5 are known to cleave versican at multiple sites in addition to the canonical site studied here.39 We, therefore, attempted to demonstrate that proteolytic fragments containing the G3 domain of versican were released into the circulation, as was previously shown.8 For this, we collected samples from the LCPR, choosing an IPAH/HPAH cohort that resembled the existing tissue cohort (Plasma Cohort I, Table 1) and that had received PAH-specific treatment.