Summary
Platelet-derived growth factor (PDGF) is a major mediator of neointima formation after
arterial injury. We constructed a recombinant adenovirus, Ad/PDGFtr, that expresses
the soluble extracellular domain of the murine PDGFβ receptor (PDGFtr). The expressed
PDGFtr was appropriately glycosylated and secreted by chicken vascular smooth muscle
cells (SMCs) in vitro. The expressed PDGFtr inhibited human PDGF-BB induced receptor
autophosphorylation, and also inhibited PDGF-BB induced cell proliferation without
affecting PDGF-AA induced mitogenesis. In vivo transduction of balloon-injured rooster
femoral arteries with Ad/PDGFtr resulted in expression and secretion of the glycosylated
PDGFtr. The expressed PDGFtr significantly inhibited neointima formation compared
with controls. Neointima-associated thrombus was significantly reduced in Ad/PDGFtr
transduced arteries compared with controls. Thus, in addition to impacting on SMC
proliferation and migration, PDGF-BB plays a role in thrombus formation in response
to arterial injury. Growth factor inhibition by localized gene delivery constitutes
a powerful approach to intervene in the molecular pathways involved in vascular disease.
Keywords
Platelet-derived growth factor - mitogenesis - thrombosis - angioplasty