Tenascin-C, a glycoprotein that crosslinks HA-lectican complexes, is a high-affinity ligand for the versican G3 domain.22,23 Although predominantly expressed during embryonic development, tenascin-C is expressed during wound healing and in vascular disease.24,25 Even though elevated levels of HA and tenascin-C were reported in PAH, their localization and spatial relationship to versican in PAH vascular lesions had yet to be elucidated. Here, VCAN is linked to pulmonary arterial hypertension.