Morphological stability, cellular viability and stem cell marker expression of three-dimensional cultures of stem cells from bone marrow and periodontium

The aim of the present study was to evaluate the morphology, cellular viability and stem cell marker expression of three-dimensional cultures of bone marrow and gingiva-derived stem cells in different ratios. Stem cell spheroids were made with bone marrow and gingiva-derived stem cells using ratios of 6:0 (Group 1), 4:2 (Group 2), 3:3 (Group 3), 2:4 (Group 4) and 0:6 (Group 5), respectively. The viability of cell spheroids was analyzed using a Live/Dead kit assay and a Cell Counting Kit-8 assay. Total RNA extraction and reverse transcription-quantitative PCR were performed to detect the mRNA expression levels of Nanog and β-actin in each group. Stem cell spheroids were well formed in silicone elastomer-based concave microwells with different ratios of bone marrow and gingiva-derived stem cells. The shape of the spheroids and their viability were maintained throughout the entirety of the experimental procedure. Statistically significant increases in spheroid diameters were noted in Groups 4 and 5 on day 1 when compared with Group 1 on day 1. There was a significant increase in the cell viability values seen in Group 3 on day 1 when compared with Group 1 on day 1. Highest levels of Nanog expression was seen in Group 3 on day 10, but the increase was not significant when compared with Group 1 on day 1. Co-culturing with higher ratios of gingiva-derived stem cells produced stem cell spheroids with larger diameters and increased cellular viability. This co-culture technique may be used in stem cell therapy with allogenic stem cell transplantation.