title: Fibrin-polyurethane composites for articular cartilage tissue engineering: a preliminary analysis.
abstract: In this study we investigated the use of a fibrin hydrogel to improve the potential of a polyurethane (PU) scaffold-based system for articular cartilage tissue engineering. PU-only ("no-fibrin") and PU-fibrin ("fibrin") composites were cultured for up to 28 days and analyzed for DNA content, glycosaminoglycan (GAG) content, type II collagen content, GAG release, and gene expression of aggrecan, collagen I, and collagen II. The use of fibrin allowed for higher viable cell-seeding efficiency (10% higher DNA content on day 2 in fibrin versus no-fibrin composites) and more even cell distribution on seeding, a more than 3-fold increase in the percentage of newly synthesized GAG retained in the constructs, and 2- to 6-fold higher levels of type II collagen and aggrecan gene expression through day 14. Addition of aprotinin to the medium inhibited fibrin degradation, most noticeably in the center of the constructs, but had little effect on biochemical composition or gene expression. Short-term mechanical compression (0-10% sinusoidal strain at 0.1 Hz for 1 h, applied twice daily for 3 days) doubled the rate of GAG release from the constructs, but had little effect on gene expression, regardless of the presence of fibrin. Although further work is needed to optimize this system, the addition of fibrin hydrogel to encapsulate cells in the stiff, macroporous PU scaffold is a step forward in our approach to articular cartilage tissue engineering.
authors.affiliation: Biochemistry and Cell Biology, AO Research Institute, Davos, Switzerland.
authors.forename: Cynthia R
authors.initials: CR
authors.lastname: Lee
authors.forename: Sibylle
authors.initials: S
authors.lastname: Grad
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Gorna
authors.forename: Sylwester
authors.initials: S
authors.lastname: Gogolewski
authors.forename: Andreas
authors.initials: A
authors.lastname: Goessl
authors.forename: Mauro
authors.initials: M
authors.lastname: Alini
mesh_terms: D053674:Aggrecans; D000818:Animals; D007611:Aprotinin / Q000494:pharmacology; D001672:Biocompatible Materials / Q000737:chemistry* / Q000378:metabolism; D002358:Cartilage, Articular / Q000166:cytology*; D002417:Cattle; D002470:Cell Survival; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism*; D024042:Collagen Type I / Q000032:analysis; D024043:Collagen Type II / Q000032:analysis; D019245:Compressive Strength; D004247:DNA / Q000032:analysis; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D005337:Fibrin / Q000737:chemistry* / Q000378:metabolism; D015870:Gene Expression; D006025:Glycosaminoglycans / Q000032:analysis / Q000378:metabolism; D006652:Histological Techniques; D020100:Hydrogels; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism*; D011140:Polyurethanes / Q000737:chemistry*; D011509:Proteoglycans / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D053674:Aggrecans; D001672:Biocompatible Materials; D024042:Collagen Type I; D024043:Collagen Type II; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D020100:Hydrogels; D037181:Lectins, C-Type; D011140:Polyurethanes; D011509:Proteoglycans; D005337:Fibrin; D004247:DNA; D007611:Aprotinin