title: The regulation of expanded human nasal chondrocyte re-differentiation capacity by substrate composition and gas plasma surface modification.
abstract: Optimizing re-differentiation of clinically relevant cell sources on biomaterial substrates in serum containing (S+) and serum-free (SF) media is a key consideration in scaffold-based articular cartilage repair strategies. We investigated whether the adhesion and post-expansion re-differentiation of human chondrocytes could be regulated by controlled changes in substrate surface chemistry and composition in S+ and SF media following gas plasma (GP) treatment. Expanded human nasal chondrocytes were plated on gas plasma treated (GP+) or untreated (GP-) poly(ethylene glycol)-terephthalate-poly(butylene terephthalate) (PEGT/PBT) block co-polymer films with two compositions (low or high PEG content). Total cellularity, cell morphology and immunofluorescent staining of vitronectin (VN) and fibronectin (FN) integrin receptors were evaluated, while post-expansion chondrogenic phenotype was assessed by collagen types I and II mRNA expression. We observed a direct relationship between cellularity, cell morphology and re-differentiation potential. Substrates supporting high cell adhesion and a spread morphology (i.e. GP+ and low PEG content films), resulted in a significantly greater number of cells expressing alpha5beta1 FN to alpha(V)beta3 VN integrin receptors, concomitant with reduced collagen type II/ImRNA gene expression. Substrates supporting low cell adhesion and a spherical morphology (GP- and high PEG content films) promoted chondrocyte re-differentiation indicated by high collagen type II/I gene expression and a low percentage of alpha5beta1 FN integrin expressing cells. This study demonstrates that cell-substrate interactions via alpha5beta1 FN integrin mediated receptors negatively impacts expanded human nasal chondrocyte re-differentiation capacity. GP treatment promotes cell adhesion in S+ media but reverses the ability of low PEG content PEGT/PBT substrates to maintain chondrocyte phenotype. We suggest alternative cell immobilization techniques to GP are necessary for clinical application in articular cartilage repair.
authors.affiliation: Institute for Biomedical Technology, University of Twente, Bilthoven Research Group, Prof. Bronkhorstlaan 10-D, 3723 MB, Bilthoven, The Netherlands. tim.woodfield@canterbury.ac.nz
authors.forename: Tim B F
authors.initials: TB
authors.lastname: Woodfield
authors.forename: Sylvie
authors.initials: S
authors.lastname: Miot
authors.forename: Ivan
authors.initials: I
authors.lastname: Martin
authors.forename: Clemens A
authors.initials: CA
authors.lastname: van Blitterswijk
authors.forename: Jens
authors.initials: J
authors.lastname: Riesle
mesh_terms: D000328:Adult; D001672:Biocompatible Materials / Q000737:chemistry*; D018929:Cell Culture Techniques / Q000379:methods; D002454:Cell Differentiation; D049109:Cell Proliferation; D048429:Cell Size; D002478:Cells, Cultured; D018914:Cells, Immobilized / Q000502:physiology; D019902:Chondrocytes / Q000166:cytology* / Q000502:physiology*; D016895:Culture Media, Serum-Free; D005740:Gases / Q000737:chemistry; D006358:Hot Temperature; D006801:Humans; D051457:Hyaline Cartilage / Q000166:cytology* / Q000502:physiology*; D039081:Integrin alpha5beta1 / Q000378:metabolism; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D009300:Nasal Septum / Q000166:cytology / Q000502:physiology; D011091:Polyesters / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D013499:Surface Properties; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D001672:Biocompatible Materials; D016895:Culture Media, Serum-Free; D005740:Gases; D039081:Integrin alpha5beta1; D039302:Integrin alphaVbeta3; C493255:PEGT-PBT copolymer; D011091:Polyesters; D011092:Polyethylene Glycols