title: Hydrogels derived from cartilage matrices promote induction of human mesenchymal stem cell chondrogenic differentiation.
abstract: Limited supplies of healthy autologous or allogeneic cartilage sources have inspired a growing interest in xenogeneic cartilage matrices as biological scaffolds for cartilage tissue engineering. The objectives of this study were to determine if shark and pig cartilage extracellular matrix (ECM) hydrogels can stimulate chondrocytic differentiation of mesenchymal stem cells (MSCs) without exogenous growth factors and to determine if the soluble factors retained by these ECM hydrogels are responsible. Human MSCs cultured on hydrogels from shark skull cartilage, pig articular cartilage, and pig auricular cartilage ECM had increased expression of chondrocyte markers and decreased secretion of angiogenic factors VEGF-A and FGF2 in comparison to MSCs cultured on tissue culture polystyrene (TCPS) at one week. MSCs grown on shark ECM gels had decreased type-1 collagen mRNA as compared to all other groups. Degradation products of the cartilage ECM gels and soluble factors released by the matrices increased chondrogenic and decreased angiogenic mRNA levels, indicating that the processed ECM retains biochemically active proteins that can stimulate chondrogenic differentiation. In conclusion, this work supports the use of cartilage matrix-derived hydrogels for chondrogenic differentiation of MSCs and cartilage tissue engineering. Longer-term studies and positive controls will be needed to support these results to definitively demonstrate stimulation of chondrocyte differentiation, and particularly to verify that calcification without endochondral ossification does not occur as it does in shark cartilage.
  
  
  
  The objectives of this study were to determine if shark and pig cartilage extracellular matrix (ECM) hydrogels can stimulate chondrocytic differentiation of mesenchymal stem cells (MSCs) without exogenous growth factors and to determine if the soluble factors retained by these ECM hydrogels are responsible for this induction. Sharks are an especially interesting model for cartilage regeneration because their entire skeleton is composed of cartilage and they do not undergo endochondral ossification. Culturing human MSCs on porcine and shark cartilage ECM gels directly, with ECM gel conditioned media, or degradation products increased mRNA levels of chondrogenic factors while decreasing angiogenic factors. These studies indicate that xenogeneic cartilage ECMs have potential as biodegradable scaffolds capable of stimulating chondrogenesis while preventing angiogenesis for regenerative medicine applications and that ECM species selection can yield differential effects.
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering and Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA.
authors.forename: Olivia A
authors.initials: OA
authors.lastname: Burnsed
authors.affiliation: Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA; Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
authors.forename: Zvi
authors.initials: Z
authors.lastname: Schwartz
authors.affiliation: H. Milton Stewart School of Industrial and Systems Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
authors.forename: Katherine O
authors.initials: KO
authors.lastname: Marchand
authors.affiliation: Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA.
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Hyzy
authors.affiliation: Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA.
authors.forename: René
authors.initials: R
authors.lastname: Olivares-Navarrete
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering and Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA; Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA. Electronic address: bboyan@vcu.edu.
authors.forename: Barbara D
authors.initials: BD
authors.lastname: Boyan
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000378:metabolism; D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism*; D002454:Cell Differentiation / Q000187:drug effects*; D020219:Chondrogenesis / Q000187:drug effects*; D017077:Culture Media, Conditioned / Q000494:pharmacology; D004247:DNA / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism*; D006801:Humans; D020100:Hydrogels / Q000494:pharmacology*; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D012754:Sharks; D012995:Solubility; D034421:Sus scrofa
chemical_list: D043925:Angiogenesis Inducing Agents; D017077:Culture Media, Conditioned; D020100:Hydrogels; D004247:DNA
keywords: Cartilage; Cartilage tissue engineering; ECM (extracellular matrix); Mesenchymal stem cell