title: The effect on osteoblast function of colocalized RGD and PHSRN epitopes on PEG surfaces.
abstract: Poly(ethylene glycol) hydrogels were synthesized with pendant peptide functionalities to examine the influence of synergistic peptide sequences on osteoblast adhesion, spreading, and function. Specifically, acrylated monomers were prepared that contained the peptide sequence, Arg-Gly Asp (RGD), as well as monomers with RGD plus its synergy site, Pro-His-Ser-Arg-Asn (PHSRN), linked via a polyglycine sequence to recapitulate the native spacing of fibronectin. The colocalized RGD-PHSRN sequence improved osteoblast adhesion, spreading, and focal contact formation when compared to RGD alone. In addition, proliferation, metabolic activity, and levels of alkaline phosphatase production, a common marker for osteoblast function, were statistically higher for the colocalized peptide sequences at 1 day, 1 week, and 2 weeks, when compared to control surfaces. Interestingly, increases were not observed in all areas of cell function, as extracellular matrix (ECM) production was the lowest on gels functionalized with the colocalized peptide sequence. This result was attributed to strong receptor-ligand interactions initiating signal transduction cascades that down-regulate ECM production.
authors.affiliation: Department of Chemical and Biological Engineering, University of Colorado, UCB 424, ECCH 111, Boulder, CO 80309-0424, USA.
authors.forename: Danielle S W
authors.initials: DS
authors.lastname: Benoit
authors.forename: Kristi S
authors.initials: KS
authors.lastname: Anseth
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D002448:Cell Adhesion / Q000187:drug effects; D002452:Cell Count; D049109:Cell Proliferation / Q000187:drug effects; D003599:Cytoskeleton / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism; D005353:Fibronectins / Q000737:chemistry / Q000494:pharmacology*; D022001:Focal Adhesions / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D015394:Molecular Structure; D009842:Oligopeptides / Q000737:chemistry / Q000494:pharmacology*; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology*; D011092:Polyethylene Glycols / Q000737:chemistry / Q000494:pharmacology*; D011108:Polymers / Q000138:chemical synthesis; D051381:Rats
chemical_list: D005353:Fibronectins; D009842:Oligopeptides; D010446:Peptide Fragments; D011108:Polymers; C495978:prolyl-histidyl-seryl-arginyl-asparagine; D011092:Polyethylene Glycols; C047981:arginyl-glycyl-aspartic acid; D000469:Alkaline Phosphatase