title: Cellular and molecular events during chondrogenesis of human mesenchymal stromal cells grown in a three-dimensional hyaluronan based scaffold.
abstract: Mesenchymal stromal cells (MSCs) seem to be a good alternative to chondrocytes for cartilage regeneration. To obtain new information on the sequence of cellular and molecular events during in vitro chondrogenic differentiation we analysed MSCs on a widely used hyaluronic acid biomaterial (Hyaff-11). Cellular differentiation was induced using two different concentrations of TGFbeta1 (10 and 20 ng/ml) and the process was analysed at different time points (24 h, and 7, 14, 21 and 28 days) using techniques of light and electron microscopy, real-time PCR and immunohistochemistry. We found that without TGFbeta MSCs did not survive while in the presence of TGFbeta the cells significantly proliferated from day 7 until day 28. Light and electron microscopy showed that TGFbeta at 20 ng/ml better induced the formation of cartilage-like tissue. Real-time PCR showed an increased expression of collagen type II, IX and aggrecan associated to a down-regulation of collagen type I. Immunohistochemical analysis confirmed that collagen type I was down-modulated while collagen type II increased from day 14 to day 28. These data clearly showed that higher concentrations of TGFbeta (20 ng/ml) induce chondrogenesis of MSCs on Hyaff-11 scaffold better than 10 ng/ml of TGFbeta. This process is characterized by a sequence of cellular and molecular events that deal with the in vitro formation of a cartilage-like tissue.
authors.affiliation: Laboratorio di Immunologia e Genetica, Istituti Ortopedici Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy. labimge@alma.unibo.it
authors.forename: Gina
authors.initials: G
authors.lastname: Lisignoli
authors.forename: Sandra
authors.initials: S
authors.lastname: Cristino
authors.forename: Anna
authors.initials: A
authors.lastname: Piacentini
authors.forename: Stefania
authors.initials: S
authors.lastname: Toneguzzi
authors.forename: Francesco
authors.initials: F
authors.lastname: Grassi
authors.forename: Carola
authors.initials: C
authors.lastname: Cavallo
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Zini
authors.forename: Liliana
authors.initials: L
authors.lastname: Solimando
authors.forename: Nadir
authors.initials: N
authors.lastname: Mario Maraldi
authors.forename: Andrea
authors.initials: A
authors.lastname: Facchini
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000502:physiology*; D020219:Chondrogenesis / Q000502:physiology*; D006801:Humans; D006820:Hyaluronic Acid / Q000737:chemistry*; D008422:Materials Testing; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000502:physiology*; D017154:Stromal Cells / Q000166:cytology / Q000502:physiology; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D001672:Biocompatible Materials; D006820:Hyaluronic Acid