Enhanced osteogenic differentiation potential of stem-cell spheroids created from a coculture of stem cells and endothelial cells

Purpose: This study was performed to fabricate stem-cell spheroids formed with human gingiva-derived stem cells and endothelial cells and to evaluate their viability and osteogenic differentiation potential. Materials and Methods: Gingiva-derived stem cells were isolated, and stem cells and endothelial cells with a total of 6 × 10⁵ cells were seeded into concave micromolds with different ratios of 6:0 (group 1), 4:2 (group 2), 3:3 (group 3), and 2:4 (group 4). Results: Gingiva-derived stem cells and/or endothelia cells formed spheroids in concave microwells. There was a decreasing trend in the diameter of spheroids with increasing amounts of endothelial cells, but there were no statistically significant differences between the groups. The secretion of vascular endothelial growth factor from the spheroids was noted. The results of the alkaline phosphatase activity assays showed significantly higher values for groups 2, 3, and 4 when compared with the value of group 1. Conclusions: Conclusively, stemcell spheroids formed with human gingiva-derived stem cells and endothelial cells using concave microwells enhanced osteogenic differentiation potential, and multicell spheroidbased cell delivery could be a simple and effective strategy for improving stem-cell therapy.