Background: Adipose-derived stem cells can improve fat graft survival, but there is no literature reporting whether bone marrow–derived mesenchymal stem cells enhance fat graft survival. The authors explored the feasibility of enhancing fat graft survival using bone marrow–derived mesenchymal stem cells.
Methods: Third-passage expanded rabbit bone marrow–derived mesenchymal stem cells were characterized by adipocyte and osteocyte differentiation and by CD29 and CD31 expression. Three were three groups of nude mice in this experiment: group A, mesenchymal stem cells; group B, expanded mesenchymal stem cells; group C, Dulbecco's medium as a blank control. The transplanted mixture contained 0.3 ml of adipose granule and 0.2 ml of cell components of 5 × 106 cells. Four months later, grafts were harvested, weighed, and analyzed.
Results: Expanded cells were successfully isolated and identified by fibroblast-like adherent shape and osteogenic and adipogenic differentiation. The results were 24.6 ± 3.4 percent for CD29 and 1.8 ± 0.4 percent for CD31 in group A, and 45.0 ± 4.9 percent for CD29 and 1.6 ± 0.3 percent for CD31 in group B. Fat graft survival rates were 0.2052 ± 0.0015 g, 0.1761 ± 0.0014 g, and 0.1350 ± 0.0020 g in groups A, B, and C, respectively (p < 0.05). Fat grafts in group A exhibited the best survival and morphologic integrity, uniform lipid droplets, and rich blood vessels; those in group B exhibited modest survival, less integrity, less uniform lipid droplets, and connective tissue septa; and those in group C exhibited some large bubbles, varied sizes of lipid droplets, and significant fibrous septa (p < 0.05). The vascular densities for groups A, B, and C were 30.4 ± 1.5, 27.2 ± 1.3, and 23.3 ± 1.9 capillaries/mm2, respectively (p < 0.05).
Conclusions: Bone marrow–derived mesenchymal stem cells and expanded bone marrow–derived mesenchymal stem cells are capable of improving fat graft survival; bone marrow–derived mesenchymal stem cells are more potent than expanded bone marrow–derived mesenchymal stem cells for doing so.