title: In vitro evaluation of biodegradable microspheres with surface-bound ligands.
abstract: Protein ligands were conjugated to the surface of biodegradable microspheres. These microsphere-ligand conjugates were then used in two in vitro model systems to evaluate the effect of conjugated ligands on microsphere behavior. Microsphere retention in agarose columns was increased by ligands on the microsphere surface specific for receptors on the agarose matrix. In another experiment, conjugating the lectin Ulex europaeus agglutinin 1 to the microsphere surface increased microsphere adhesion to Caco-2 monolayers compared to control microspheres. This increase in microsphere adhesion was negated by co-administration of l-fucose, indicating that the increase in adhesion is due to specific interaction of the ligand with carbohydrate receptors on the cell surface. These results demonstrate that the ligands conjugated to the microspheres maintain their receptor binding activity and are present on the microsphere surface at a density sufficient to target the microspheres to both monolayers and three-dimensional matrices bearing complementary receptors.
authors.affiliation: School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Keegan
authors.forename: Sara M
authors.initials: SM
authors.lastname: Royce
authors.forename: Tarek
authors.initials: T
authors.lastname: Fahmy
authors.forename: W Mark
authors.initials: WM
authors.lastname: Saltzman
mesh_terms: D000818:Animals; D018938:Caco-2 Cells; D002417:Cattle; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism; D008024:Ligands; D051379:Mice; D008863:Microspheres; D011100:Polyglycolic Acid / Q000378:metabolism; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D012710:Serum Albumin, Bovine / Q000378:metabolism; D013499:Surface Properties; D039762:Ulex / Q000378:metabolism
chemical_list: D008024:Ligands; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D012710:Serum Albumin, Bovine; D019344:Lactic Acid