TISSUE ENGINEERED PERIVASCULAR ENDOTHELIAL-CELL IMPLANTS REGULATE VASCULAR INJURY

Molecular biomaterial engineering permits in vivo transplantation of c ells and tissues, offering the promise of restoration of physiologic c ontrol rather than pharmacologic dosing with isolated compounds, We en grafted endothelial cells on Gelfoam biopolymeric matrices with retent ion of viability, normal growth kinetics, immunoreactivity, and bioche mical activity, The production of heparan sulfate proteoglycan and inh ibition of basic fibroblast growth factor binding and activity by engr afted cells were indistinguishable from endothelial cells grown in cul ture, Perivascular implantation of Gelfoam-endothelial cell scaffolds around balloon-denuded rat carotid arteries reduced intimal hyperplasi a 88.1%, far better than the isolated administration of heparin, the m ost effective endothelial mimic compound, In concert with a reduction in intimal area, cell proliferation was reduced by > 90%. To our knowl edge, there have been no previous reports of extravascular cell implan ts controlling vasculoproliferative disease. Tissue engineered cells o ffer the potential for potent methods of vascular growth regulation an d insight into the complex autocrine-paracrine control mechanisms with in the blood vessel wall.