Synthetic vascular prosthesis impregnated with mesenchymal stem cells overexpressing endothelial nitric oxide synthase

Abstract

BACKGROUND - Endothelial dysfunction is known to exaggerate coronary artery disease, sometimes leading to irreversible myocardial damage. In such cases, repetitive coronary revascularization including coronary artery bypass grafting is needed, which may cause a shortage of graft conduits. On the other hand, endothelial nitric oxide synthase (eNOS) is an attractive target of cardiovascular gene therapy. The vascular prostheses, of which the inner surfaces are covered with mesenchymal stem cells (MSCs) overexpressing eNOS, are expected to offer feasible effects of NO and angiogenic effects of MSCs on the native coronary arterial beds, as well as improvement of self-patency. Herein, we attempted to develop small caliber vascular prostheses generating the bioactive proteins. Also, we attempted to transduce eNOS cDNA into MSCs. METHODS AND RESULTS - The MSCs were isolated from rat bone marrow and transduced with each adenovirus harboring rat eNOS cDNA and β-galactosidase (β-gal) (eNOS/MSCs and β-gal/MSCs). The β-gal/MSCs were impregnated into vascular prostheses, then the expressions of β-gal on the inner surfaces of them were evaluated by 5-bromo-4-chloro-3-indolyl β-d-galactoside staining. The NOS activity of eNOS/MSCs was assayed by monitoring the conversion of H-arginine to H-citrulline. The inner surfaces of the vascular prostheses were covered with MSCs expressing β-gal. The amount of the H-citrulline increased, and eNOS/MSCs were determined to generate enzymatic activity of eNOS. This activity was completely inhibited by N-nitro-l-arginine methyl ester. CONCLUSIONS - The inner surface of expanded polytetrafluoroethylene vascular prostheses seeded with lacZ gene-transduced MSCs exhibited recombinant proteins. Development of eNOS/MSC-seeded vascular prostheses would promise much longer graft patency and vasculoprotective effects. © 2006 American Heart Association, Inc.