Title

Local delivery of gene vectors from bare-metal stents by use of a biodegradable synthetic complex inhibits in-stent restenosis in rat carotid arteries

UMMS Affiliation

Graduate School of Biomedical Sciences; Division of Cardiology; Department of Physiology

Date

4-17-2008

Document Type

Article

Medical Subject Headings

*Absorbable Implants; Adenoviridae; Animals; Aorta; Carotid Stenosis; Cells, Cultured; Cross-Linking Reagents; Gene Therapy; *Gene Transfer Techniques; Green Fluorescent Proteins; Male; Metals; Muscle, Smooth, Vascular; Neutralization Tests; Nitric Oxide Synthase Type II; Rats; Rats, Sprague-Dawley; Recurrence; *Stents

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

BACKGROUND: Local drug delivery from polymer-coated stents has demonstrated efficacy for preventing in-stent restenosis; however, both the inflammatory effects of polymer coatings and concerns about late outcomes of drug-eluting stent use indicate the need to investigate innovative approaches, such as combining localized gene therapy with stent angioplasty. Thus, we investigated the hypothesis that adenoviral vectors (Ad) could be delivered from the bare-metal surfaces of stents with a synthetic complex for reversible vector binding.

METHODS AND RESULTS: We synthesized the 3 components of a gene vector binding complex: (1) A polyallylamine bisphosphonate with latent thiol groups (PABT), (2) a polyethyleneimine (PEI) with pyridyldithio groups for amplification of attachment sites [PEI(PDT)], and (3) a bifunctional (amine- and thiol-reactive) cross-linker with a labile ester bond (HL). HL-modified Ad attached to PABT/PEI(PDT)-treated steel surfaces demonstrated both sustained release in vitro over 30 days and localized green fluorescent protein expression in rat arterial smooth muscle cell cultures, which were not sensitive to either inhibition by neutralizing anti-Ad antibodies or inactivation after storage at 37 degrees C. In rat carotid studies, deployment of steel stents configured with PABT/PEI(PDT)/HL-tethered adenoviral vectors demonstrated both site-specific arterial Ad(GFP) expression and adenovirus-luciferase transgene activity per optical imaging. Rat carotid stent delivery of adenovirus encoding inducible nitric oxide synthase resulted in significant inhibition of restenosis.

CONCLUSIONS: Reversible immobilization of adenovirus vectors on the bare-metal surfaces of endovascular stents via a synthetic complex represents an efficient, tunable method for sustained release of gene vectors to the vasculature.

Rights and Permissions

Citation: Circulation. 2008 Apr 22;117(16):2096-103. Epub 2008 Apr 14. Link to article on publisher's site

Related Resources

Link to Article in PubMed