In vitro engineered cartilage using synovium-derived mesenchymal stem cells with injectable gellan hydrogels

Area of Science:

• Biomaterials Science
• Stem Cell Biology
• Tissue Engineering

Background:

• Synovium-derived mesenchymal stem cells (SMSC) are a promising source for cartilage tissue engineering.
• Injectable hydrogels offer potential for minimally invasive cartilage repair strategies.

Purpose of the Study:

• To investigate the efficacy of rabbit SMSC encapsulated in injectable gellan hydrogels for in vitro engineered cartilage formation.
• To evaluate the effects of TGF-beta1, TGF-beta3, and BMP-2 on SMSC chondrogenesis within gellan hydrogels.

Main Methods:

• Isolation and expansion of rabbit SMSC.
• Encapsulation of SMSC in injectable gellan hydrogels.
• Culture of constructs in chondrogenic medium with specific growth factors (TGF-beta1, TGF-beta3, BMP-2) for up to 42 days.
• Assessment of cell proliferation, chondrocytic gene/protein expression, and matrix deposition using WST-1 assay, RT-PCR, biochemical analysis, histology, and immunohistochemistry.

Main Results:

• SMSC viability remained high in hydrogels treated with TGF-beta1, TGF-beta3, and BMP-2.
• Cartilaginous tissue formation and expression of chondrocytic markers (collagen type II, aggrecan, SOX 9) were observed as early as 21 days.
• TGF-beta1 and TGF-beta3 treatments resulted in greater chondrogenesis compared to BMP-2.

Conclusions:

• Injectable SMSC-laden gellan hydrogels are competent for in vitro engineered cartilage formation.
• Growth factors TGF-beta1 and TGF-beta3 enhance chondrogenesis in this system.
• This approach provides a foundation for potential clinical applications in cartilage repair.