title: Proteolytically degradable hydrogels with a fluorogenic substrate for studies of cellular proteolytic activity and migration.
abstract: We have developed proteolytically degradable hydrogels with covalently immobilized fluorogenic protease substrates to visualize extracellular proteolytic activity and cell migration in three dimensions. Dye quenched-bovine serum albumin (DQ-BSA), a quenched, proteolytically activated fluorogenic substrate, was conjugated to poly(ethylene glycol) (PEG)-monoacrylate, and the product (DQ-BSA-PEG) was then covalently incorporated into proteolytically degradable and cell adhesive PEG hydrogels via photopolymerization. The DQ-BSA-PEG substrate in solution and incorporated into hydrogels exhibited significantly enhanced fluorescence after exposure to enzymes. Fibroblasts seeded within this hydrogel spread in three dimensions and extended lamellipodia. Cell migration and proteolytic activity were visualized using confocal microscopy. Proteolytic activity was concentrated near cell surfaces and remained present in the tracks where cell migration had occurred.
authors.affiliation: Department of Bioengineering, Rice University, P.O. Box 1892, MS 142, Houston, Texas 77251-1892, USA.
authors.forename: Soo-Hong
authors.initials: SH
authors.lastname: Lee
authors.forename: Jordan S
authors.initials: JS
authors.lastname: Miller
authors.forename: James J
authors.initials: JJ
authors.lastname: Moon
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: West
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry; D001673:Biodegradation, Environmental; D001709:Biotechnology; D002417:Cattle; D002465:Cell Movement; D002478:Cells, Cultured; D005456:Fluorescent Dyes; D006801:Humans; D020100:Hydrogels / Q000138:chemical synthesis / Q000737:chemistry; D008422:Materials Testing; D018613:Microscopy, Confocal; D010447:Peptide Hydrolases / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000138:chemical synthesis / Q000737:chemistry; D012710:Serum Albumin, Bovine
chemical_list: D001672:Biocompatible Materials; D005456:Fluorescent Dyes; D020100:Hydrogels; D012710:Serum Albumin, Bovine; D011092:Polyethylene Glycols; D010447:Peptide Hydrolases