title: Targeting microspheres and cells to polyethylene glycol-modified biological surfaces.
abstract: It has previously been demonstrated that damaged arterial tissue can be acutely modified with protein-reactive polyethylene glycol (PEG) to block undesirable platelet deposition. This concept might be expanded by employing PEG-biotin and its strong interaction with avidin for site-specific targeted delivery. Toward this end, cultured endothelial cells (ECs) were surface modified with PEG-biotin and the available biotin was quantified with flow cytometry. NeutrAvidin-coated microspheres and PEG-biotin modified ECs with NeutrAvidin as a bridging molecule were delivered under arterial shear stress to PEG-biotin modified ECs on a coverslip as well as scrape-damaged bovine carotid arteries. After incubation with a 10 mM solution for 1 min, 8 x 10(7) PEG-biotin molecules/EC were found and persisted for up to 120 h. Perfused microspheres adhered to NHS-PEG-biotin treated bovine carotid arteries with 60 +/- 16 microspheres/mm(2) versus 11 +/- 4 microspheres/mm(2) for control arteries (p < 0.015). Similarly, 22 +/- 5 targeted ECs/mm(2) adhered to NHS-PEG-biotin treated bovine carotid arteries versus 6 +/- 2 ECs/mm(2) for control arteries (p < 0.01). The targeting strategy demonstrated here might ultimately find application for drug delivery, gene therapy, or cell therapy where localization to specific labeled vascular regions is desired following catheter-based or surgical procedures.
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Deglau
authors.forename: Jermaine D
authors.initials: JD
authors.lastname: Johnson
authors.forename: Flordeliza S
authors.initials: FS
authors.lastname: Villanueva
authors.forename: William R
authors.initials: WR
authors.lastname: Wagner
mesh_terms: D000818:Animals; D001158:Arteries / Q000473:pathology; D001710:Biotin / Q000737:chemistry; D002417:Cattle; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D008863:Microspheres; D011092:Polyethylene Glycols / Q000378:metabolism* / Q000494:pharmacology; D013499:Surface Properties
chemical_list: D011092:Polyethylene Glycols; D001710:Biotin