title: Effect of matrix elasticity on the maintenance of the chondrogenic phenotype.
abstract: The aim of this study was to examine the influence of matrix elasticity on the maintenance of the chondrogenic phenotype of chondrocytes cultured in monolayer. We used a two-dimensional culturing system in which polyacrylamide gels with different concentrations of bis-acrylamide were coated with collagen type I. Matrices with a Young's modulus of 4, 10, 40, and 100 kPa were produced, as determined by atomic force microscopy. Porcine chondrocytes were cultivated on these matrices at a low density for 7 days. The proliferation of cells was analyzed by 5-Bromo-2'-deoxy-uridine incorporation. Maintenance of the chondrogenic phenotype was analyzed by measuring collagen type I, type II, and aggrecan gene expression, immunofluorescence staining for collagen type II, and phalloidin staining for actin filaments. Cellular proliferation and actin organization were decreased on matrices of 4 kPa compared with stiffer substrates. The differentiated phenotype of the chondrocytes grown on matrices of 4 kPa was stabilized, indicated by higher collagen type II and aggrecan, and lower collagen type I expression. These findings indicate that chondrocytes sense the elasticity of the matrix and might be used for the design of scaffolds with mechanical properties specifically tailored to support the chondrogenic phenotype in tissue engineering applications.
authors.affiliation: Institute of Virology and Cell Biology, University of Lübeck , Lübeck, Germany .
authors.forename: Elena
authors.initials: E
authors.lastname: Schuh
authors.forename: Jan
authors.initials: J
authors.lastname: Kramer
authors.forename: Jürgen
authors.initials: J
authors.lastname: Rohwedel
authors.forename: Holger
authors.initials: H
authors.lastname: Notbohm
authors.forename: Ralph
authors.initials: R
authors.lastname: Müller
authors.forename: Thomas
authors.initials: T
authors.lastname: Gutsmann
authors.forename: Nicole
authors.initials: N
authors.lastname: Rotter
mesh_terms: D000180:Acrylic Resins; D000199:Actins / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D049109:Cell Proliferation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000502:physiology*; D020219:Chondrogenesis / Q000235:genetics / Q000502:physiology; D003094:Collagen; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D055119:Elastic Modulus; D004548:Elasticity; D005109:Extracellular Matrix / Q000502:physiology*; D005782:Gels; D010641:Phenotype; D034421:Sus scrofa; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds
chemical_list: D000180:Acrylic Resins; D000199:Actins; D024042:Collagen Type I; D024043:Collagen Type II; D017931:DNA Primers; D005782:Gels; C016680:polyacrylamide gels; D003094:Collagen