Addition of Adipose-Derived Stem Cells to Mesenchymal Stem Cell Sheets Improves Bone Formation at an Ectopic Site

Abstract

To determine the effect of adipose-derived stem cells (ADSCs) added to bone marrow-derived mesenchymal stem cell (MSC) sheets on bone formation at an ectopic site. We isolated MSCs and ADSCs from the same rabbits. We then prepared MSC sheets for implantation with or without ADSCs subcutaneously in the backs of severe combined immunodeficiency (SCID) mice. We assessed bone formation at eight weeks after implantation by micro-computed tomography and histological analysis. In osteogenic medium, MSCs grew to form multilayer sheets containing many calcium nodules. MSC sheets without ADSCs formed bone-like tissue; although neo-bone and cartilage-like tissues were sparse and unevenly distributed by eight weeks after implantation. In comparison, MSC sheets with ADSCs promoted better bone regeneration as evidenced by the greater density of bone, increased mineral deposition, obvious formation of blood vessels, large number of interconnected ossified trabeculae and woven bone structures, and greater bone volume/total volume within the composite constructs. Our results indicate that although sheets of only MSCs have the potential to form tissue engineered bone at an ectopic site, the addition of ADSCs can significantly increase the osteogenic potential of MSC sheets. Thus, the combination of MSC sheets with ADSCs may be regarded as a promising therapeutic strategy to stimulate bone regeneration.

Culture‐expanded mesenchymal stem cell sheets enhance extraction‐site alveolar bone growth: An animal study

“…Our data partially confirmed this hypothesis by demonstrating that transplantation of autogenous culture‐expanded MSC sheets to the buccal surface of extraction sites increased surface bone density (Figures and ), while its effect on surface thickness and mineral apposition was statistically insignificant (Figures and ). The average net increase in surface TMD (53%; Figure A) and BV/TV (22%; Figure B) at the MSC sheet side relative to the control side is somewhat comparable with recent reports from Wang et al . They transplanted autogenous MSC sheets to an ectopic subcutaneous location in a rabbit model and assessed the osteogenic outcome 8 weeks later, and found that the regenerated bone tissue accounted for 36% of the total area of the region of interest.…”

Effect of Cell Seeding Density and Inflammatory Cytokines on Adipose Tissue-Derived Stem Cells: an in Vitro Study

“…We used the seeding density of 8000 cells/cm 2 as a control in this experiment, since this seeding density is often used for expansion [7]. The seeding densities 20,000, 50,000 and 400,000 cells/cm 2 were selected based on previous studies examining cell sheets [10, 26, 36]. After overnight attachment, we refreshed the cells with LG-DMEM with 1% FBS, 50 μg/ml gentamicin and 1.5 μg/ml fungizone® (control condition).…”

Bone marrow‐derived stem/stromal cells and adipose tissue‐derived stem/stromal cells: Their comparative efficacies and synergistic effects

“…Conversely, BMSC sheets containing ADSCs produced better regenerated bone as evidenced by greater bone densities, increased mineral deposition, obvious formation of blood vessels, large numbers of interconnected ossified trabeculae and woven bone structures, and greater bone volume: total volume ratios within the composite constructs. These results showed the addition of ADSCs can significantly increase the osteogenic potential of BMSC sheets …”