Randolph L. Geary, MD
Professor of Vascular and Endovascular Surgery, Pathology (Comparative Medicine) and Institute for Regenerative Medicine; Director, Vascular Biology Laboratory (Vascular Surgery)
Tel: (336) 716-9502
Artery Wall Remodeling and Restenosis
While much is known about the regulation of smooth muscle cell neointimal hyperplasia, little is known about the molecular regulation of artery wall remodeling and constriction. Our lab is studying the effects of various matrix components on tissue contraction. Specifically, we are studying the interaction between cells, collagen, and hyaluronan - a prominent component of the matrix secreted by smooth muscle cells as they repair artery wall injury. Hyaluronan may improve reorganization of collagen following injury. To address this question we are studying the impact of hyaluronan and its receptors (e.g. RHAMM and CD44) and smooth muscle signaling and collagen remodeling in vitro and artery wall remodeling after injury in mice lacking specific hyaluronan receptors. The overarching goal is to identify molecular targets to block constrictive remodeling after arterial reconstruction as a means of preventing restenosis.
Our lab is also collaborating with the Wake Forest Institute of Regenerative Medicine to characterize progenitor cells and their application in creating bioengineered blood vessels using autologous cells seeded onto tubular scaffolds. After a period of preconditioning to flow and pressure in a bioreactor, vessels are implanted as arterial interposition grafts or AV shunt grafts in animal models (primate, ovine and rabbit). Many parallels are likely involved in the healing of bioengineered arteries and healing in native arteries after reconstruction. By manipulating cells and scaffold materials used in constructing bioengineered blood vessels, we may be able to alter healing responses to improve vessel maturation.