Regulation of stem cells by transforming growth factor Β3/polylactic acid-glycolic acid microspheres / 中国组织工程研究

ABSTRACT

BACKGROUND: Transforming growth factor Β3/polylactic acid-glycolic acid (TGF-Β3/PLGA) sustained-release microspheres can maintain the effective drug concentration at the site of action and provide the feasibility for efficient utilization of growth factors. OBJECTIVE: To optimize the manufacturing process of TGF-Β3/PLGA sustained-release microspheres, and investigate their effects on the proliferation and migration of rabbit adipose-derived mesenchymal stem cells (ADSCs). METHODS: TGF-Β3/PLGA sustained-release microspheres were prepared by emulsification-solvent evaporation method. The morphology, particle size, drug spatial distribution, encapsulation efficiency, drug loading, and sustained release properties of the microspheres were characterized. The TGF-Β3/PLGA sustained-release microspheres were dissolved in phosphate buffered saline. The concentration of TGF-Β3 in the supernatant was detected at the corresponding time points. The microsphere morphology was observed by scanning electron microscopy at the corresponding time point. Adipose-derived mesenchymal stem cells were divided into six groups and then cultured with single culture medium (negative control) or culture medium containing TGF-Β3 or blank PLGA, or culture medium containing 10,100,1 000 g/L TGF-Β3/PLGA microspheres. Cell proliferation was detected by CCK-8 assay at the corresponding time point. Cells in each group were cultured for 24 hours with corresponding medium in a non-contact manner. The number of migratory cells was counted. RESULTS AND CONCLUSION: (1) TGF-Β3/PLGA sustained-release microspheres were spherical with smooth surface, no adhesion, and evenly distributed particle size. The microspheres had a diameter of 2-50 µm, and the protein drugs in the microspheres were evenly distributed, with high encapsulation efficacy and encapsulation dose. (2) The TGF-Β3/PLGA sustained-release microspheres had good degradation properties and were completely degraded after 6 months in vitro. At the same time, these microspheres had good sustained-release performance and released TGF-Β3 slowly for 45 days in vitro. (3) Blank microspheres and the sustained-release microspheres containing TGF-Β3 had no effect on the proliferation of adipose-derived mesenchymal stem cells. (4) Blank microspheres had no effect on the migration of adipose-derived mesenchymal stem cells, and the transforming growth factor 3 and the sustained-release microspheres containing TGF-Β3 promoted the migration of adipose-derived mesenchymal stem cells. There was no significant difference in the migration promotion between different concentrations of TGF-Β3. (5) These findings suggest that the TGF-Β3/PLGA sustained-release microspheres can promote the migration of adipose-derived mesenchymal stem cells without affecting their proliferation.