title: Cell response to RGD density in cross-linked artificial extracellular matrix protein films.
abstract: This study examines the adhesion, spreading, and migration of human umbilical vein endothelial cells on cross-linked films of artificial extracellular matrix (aECM) proteins. The aECM proteins described here were designed for application in small-diameter grafts and are composed of elastin-like structural repeats and fibronectin cell-binding domains. aECM-RGD contains the RGD sequence derived from fibronectin; the negative control protein aECM-RDG contains a scrambled cell-binding domain. The covalent attachment of poly(ethylene glycol) (PEG) to aECM substrates reduced nonspecific cell adhesion to aECM-RDG-PEG but did not preclude sequence-specific adhesion of endothelial cells to aECM-RGD-PEG. Variation in ligand density was accomplished by the mixing of aECM-RGD-PEG and aECM-RDG-PEG prior to cross-linking. Increasing the density of RGD domains in cross-linked films resulted in more robust cell adhesion and spreading but did not affect cell migration speed. Control of cell-binding domain density in aECM proteins can thus be used to modulate cell adhesion and spreading and will serve as an important design tool as these materials are further developed for use in surgery, tissue engineering, and regenerative medicine.
authors.affiliation: Division of Chemistry and Chemical Engineering, Joseph J. Jacobs Institute for Molecular Engineering for Medicine, California Institute of Technology, Mail Code 210-41, Pasadena, California 91125, USA.
authors.forename: Julie C
authors.initials: JC
authors.lastname: Liu
authors.forename: David A
authors.initials: DA
authors.lastname: Tirrell
mesh_terms: D001665:Binding Sites; D040761:Biomimetic Materials / Q000737:chemistry*; D001807:Blood Vessel Prosthesis; D002448:Cell Adhesion; D002465:Cell Movement; D042783:Endothelial Cells / Q000166:cytology*; D016326:Extracellular Matrix Proteins / Q000737:chemistry*; D006801:Humans; D009842:Oligopeptides; D011092:Polyethylene Glycols; D015202:Protein Engineering; D014471:Umbilical Veins / Q000166:cytology
chemical_list: D016326:Extracellular Matrix Proteins; D009842:Oligopeptides; D011092:Polyethylene Glycols; C047981:arginyl-glycyl-aspartic acid