title: Bisphosphonate-mediated gene vector delivery from the metal surfaces of stents.
abstract: The clinical use of metallic expandable intravascular stents has resulted in improved therapeutic outcomes for coronary artery disease. However, arterial reobstruction after stenting, in-stent restenosis, remains an important problem. Gene therapy to treat in-stent restenosis by using gene vector delivery from the metallic stent surfaces has never been demonstrated. The present studies investigated the hypothesis that metal-bisphosphonate binding can enable site-specific gene vector delivery from metal surfaces. Polyallylamine bisphosphonate (PAA-BP) was synthesized by using Michael addition methodology. Exposure to aqueous solutions of PAA-BP resulted in the formation of a monomolecular bisphosphonate layer on metal alloy surfaces (steel, nitinol, and cobalt-chromium), as demonstrated by x-ray photoelectron spectroscopy. Surface-bound PAA-BP enabled adenoviral (Ad) tethering due to covalent thiol-binding of either anti-Ad antibody or a recombinant Ad-receptor protein, D1. In arterial smooth muscle cell cultures, alloy samples configured with surface-tethered Ad were demonstrated to achieve site-specific transduction with a reporter gene, (GFP). Rat carotid stent angioplasties using metal stents exposed to aqueous PAA-BP and derivatized with anti-knob antibody or D1 resulted in extensive localized Ad-GFP expression in the arterial wall. In a separate study with a model therapeutic vector, Ad-inducible nitric oxide synthase (iNOS) attached to the bisphosphonate-treated metal stent surface via D1, significant inhibition of restenosis was demonstrated (neointimal/media ratio 1.68 +/- 0.27 and 3.4 +/- 0.35; Ad-iNOS vs. control, P < 0.01). It is concluded that effective gene vector delivery from metallic stent surfaces can be achieved by using this approach.
authors.affiliation: Division of Cardiology, The Children's Hospital of Philadelphia, Department of Chemical, Philadelphia, PA 19104, USA.
authors.forename: Ilia
authors.initials: I
authors.lastname: Fishbein
authors.forename: Ivan S
authors.initials: IS
authors.lastname: Alferiev
authors.forename: Origene
authors.initials: O
authors.lastname: Nyanguile
authors.forename: Richard
authors.initials: R
authors.lastname: Gaster
authors.forename: John M
authors.initials: JM
authors.lastname: Vohs
authors.forename: Gordon S
authors.initials: GS
authors.lastname: Wong
authors.forename: Howard
authors.initials: H
authors.lastname: Felderman
authors.forename: I-Wei
authors.initials: IW
authors.lastname: Chen
authors.forename: Hoon
authors.initials: H
authors.lastname: Choi
authors.forename: Robert L
authors.initials: RL
authors.lastname: Wilensky
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Levy
mesh_terms: D000256:Adenoviridae / Q000378:metabolism; D017130:Angioplasty / Q000379:methods*; D000818:Animals; D002478:Cells, Cultured; D003324:Coronary Artery Disease / Q000150:complications / Q000601:surgery*; D004164:Diphosphonates / Q000378:metabolism*; D017930:Genes, Reporter / Q000235:genetics; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000378:metabolism / Q000627:therapeutic use*; D006083:Graft Occlusion, Vascular / Q000209:etiology / Q000628:therapy*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D008297:Male; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D011073:Polyamines / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013057:Spectrum Analysis; D015607:Stents; D014161:Transduction, Genetic / Q000379:methods
chemical_list: D004164:Diphosphonates; D011073:Polyamines; D049452:Green Fluorescent Proteins; C063994:polyallylamine; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat