title: Good manufacturing practice-grade fibrin gel is useful as a scaffold for human mesenchymal stromal cells and supports in vitro osteogenic differentiation.
abstract: BACKGROUND
  Recently, there has been an increased interest in using mesenchymal stromal cells (MSCs) in bone tissue engineering coupled with a suitable scaffold of both biological and synthetic origin. The cells and these constructs can be combined in vitro or directly in vivo to enhance tissue repair. MSCs are spindle-shaped cells capable of self-renewal and can be induced to differentiate mainly into osteo-, chondro-, and adipogenic-progeny types. Several biomaterials are currently available and, among them, fibrin-based constructs seem to be suitable for guiding the cells during tissue repair or regeneration due to their biocompatibility and biodegradability.
  
  
  METHODS
  Here, this study describes a simple in vitro system using human mesenchymal stromal cells (hMSCs) and fibrin scaffold prepared at different concentrations in fibrinogen (1.5%-3% and 6%) to evaluate cell proliferation and viability inside these constructs.
  
  
  RESULTS
  The data demonstrate that the constructs with 3 percent in fibrinogen resulted in the best scaffolds, because within them the cells were able to proliferate and were uniformly distributed. Finally, analyzing the capability of the clots to support osteogenic differentiation of MSCs, we observed that they differentiated into osteoblasts.
  
  
  CONCLUSIONS
  These results suggest that fibrin gel could be useful as a delivery system for hMSCs.
authors.affiliation: Department of Oncology, Transplant and Advanced Technologies in Medicine, Hematology Division, University of Pisa, Pisa, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Trombi
authors.forename: Delfo
authors.initials: D
authors.lastname: D'Alessandro
authors.forename: Simone
authors.initials: S
authors.lastname: Pacini
authors.forename: Bruno
authors.initials: B
authors.lastname: Fiorentino
authors.forename: Manuela
authors.initials: M
authors.lastname: Scarpellini
authors.forename: Rita
authors.initials: R
authors.lastname: Fazzi
authors.forename: Sara
authors.initials: S
authors.lastname: Galimberti
authors.forename: Stefano
authors.initials: S
authors.lastname: Guazzini
authors.forename: Mario
authors.initials: M
authors.lastname: Petrini
mesh_terms: D015415:Biomarkers; D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation; D002455:Cell Division; D002470:Cell Survival; D005337:Fibrin; D005340:Fibrinogen; D005782:Gels; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D010006:Osteoblasts / Q000166:cytology*; D017154:Stromal Cells / Q000166:cytology*
chemical_list: D015415:Biomarkers; D005782:Gels; D005337:Fibrin; D005340:Fibrinogen