Fibro/chondrogenic differentiation of dental stem cells into chitosan/alginate scaffolds towards temporomandibular joint disc regeneration

J Mater Sci Mater Med. 2018 Jun 26;29(7):97. doi: 10.1007/s10856-018-6109-6.

Abstract

Tissue engineering (TE) may provide effective alternative treatment for challenging temporomandibular joint (TMJ) pathologies associated with disc malpositioning or degeneration and leading to severe masticatory dysfunction. Aim of this study was to evaluate the potential of chitosan/alginate (Ch/Alg) scaffolds to promote fibro/chondrogenic differentiation of dental pulp stem cells (DPSCs) and production of fibrocartilage tissue, serving as a replacement of the natural TMJ disc. Ch/Alg scaffolds were fabricated by crosslinking with CaCl2 combined or not with glutaraldehyde, resulting in two scaffold types that were physicochemically characterized, seeded with DPSCs or human nucleus pulposus cells (hNPCs) used as control and evaluated for cell attachment, viability, and proliferation. The DPSCs/scaffold constructs were incubated for up to 8 weeks and assessed for extracellular matrix production by means of histology, immunofluorescence, and thermomechanical analysis. Both Ch/Alg scaffold types with a mass ratio of 1:1 presented a gel-like structure with interconnected pores. Scaffolds supported cell adhesion and long-term viability/proliferation of DPSCs and hNPCs. DPSCs cultured into Ch/Alg scaffolds demonstrated a significant increase of gene expression of fibrocartilaginous markers (COLI, COL X, SOX9, COM, ACAN) after up to 3 weeks in culture. Dynamic thermomechanical analysis revealed that scaffolds loaded with DPSCs significantly increased storage modulus and elastic response compared to cell-free scaffolds, obtaining values similar to those of native TMJ disc. Histological data and immunochemical staining for aggrecan after 4 to 8 weeks indicated that the scaffolds support abundant fibrocartilaginous tissue formation, thus providing a promising strategy for TMJ disc TE-based replacement.

MeSH terms

  • Alginates
  • Biomechanical Phenomena
  • Cell Differentiation
  • Cell Proliferation
  • Cell Survival
  • Cells, Cultured
  • Chitosan
  • Chondrogenesis
  • Dental Pulp / cytology*
  • Elastic Modulus
  • Glucuronic Acid
  • Hexuronic Acids
  • Humans
  • Joint Prosthesis
  • Materials Testing
  • Microscopy, Electron, Scanning
  • Regeneration
  • Stem Cells / cytology*
  • Temporomandibular Joint Disc / cytology
  • Temporomandibular Joint Disc / physiology*
  • Temporomandibular Joint Disc / surgery
  • Tissue Engineering
  • Tissue Scaffolds* / chemistry

Substances

  • Alginates
  • Hexuronic Acids
  • Glucuronic Acid
  • Chitosan