Construction and characterization of osteogenic and vascular endothelial cell sheets from rat adipose-derived mesenchymal stem cells.

In this study, adipose-derived mesenchymal stem cells (ADSCs) were isolated from adipose tissues of rats. Flow cytometry identification showed that ADSCs of passage 3 highly expressed CD29 and CD44, but hardly expressed CD31 and CD45. Adipogenic, osteogenic, and chondrogenic differentiation were confirmed by the results of oil red O staining, alkaline phosphatase (ALP), and alcian blue staining, respectively. ADSCs at a density of 1×10(6)/cm(2) were cultured in the osteogenic medium and the osteogenic cell sheets could be obtained after 14 d. The cell sheets were positive with von kossa staining. The transmission electron microscopy (TEM) result showed that needle-like calcium salt crystals were deposited on the ECM. These results suggested that the osteogenic cell sheets may have potential osteogenesis ability. ADSCs at a density of 1×10(6)/cm(2) were cultured in the endothelial cell growth medium-2 and the endothelial cell sheets can be formed after 16 d of culture. The TEM image confirmed that the Weibel-Palade corpuscle was seen in the cells. The expression of CD31 was positive, suggesting that the endothelial cell sheets may have a strong ability to form blood vessels. In this study, two types of cell sheets with the potential abilities of osteogenesis and blood vessels formation were obtained by induced culture of ADSCs in vitro, which lays a foundation to build vascularized tissue engineered bone for the therapy of bone defects.

Bilayered PLGA/Wool Keratin Composite Membranes Support Periodontal Regeneration in Beagle Dogs.

Regenerative procedures using guided tissue regeneration (GTR) membrane are presently well-established in periodontal therapy. In this study, bilayered poly(lactic-co-glycolic acid) (PLGA)/wool keratin (WK) composite membranes were prepared for use as GTR membrane by the solvent casting and electrospinning methods. Then, the composite membranes were used to evaluate the effects in guided tissue regeneration in beagle dogs. The results showed that the bottom layer (casting film) of the bilayered PLGA/wool keratin composite membranes was a compact PLGA/wool keratin membrane, and the upper layer (electrospun film) was a loose, porous, three-dimensional, and fibrous PLGA/wool keratin membrane (The wool keratin was at five different levels: 0, 0.5, 1, 2, or 4 wt %). The mechanical properties of the composites were significantly enhanced by the addition of wool keratin. The bilayered PLGA/1.0% wool keratin composite membranes presented the best values of ultimate strength and Young's modulus. All of the bilayered PLGA/wool keratin composite membranes showed high thermal and thermooxidative stabilities. The GTR results showed that the PLGA/1.0% wool keratin composite membranes could effectively promote the periodontal tissue regeneration after 12 weeks, and have a similar effect to the collagen membrane on the regeneration of the periodontal tissue. Thus, the bilayered PLGA/wool keratin composite membranes show great potential to meet the demand for GTR membrane. The study will serve as a foundation for further study of the PLGA/wool keratin membranes for GTR application and the therapy of periodontal disease.