ABSTRACT
INTRODUCTION: Tissue expansion has been applied in tissue repair and reconstruction of large soft tissue defects. Stromal vascular fraction (SVF) transplantation is a promising treatment in raising expansion efficiency. However, the clinical utilization of SVF is limited because of its conventional collagenase-based production. The aim of this study was to evaluate the effect of emulsified fat (EF), SVF obtained by using mechanical method, on accelerating tissue expansion. MATERIALS AND METHODS: The microstructure of EF fragments and the proportion of mesenchymal stem cells (MSCs; CD45-/CD34+) in EF were detected. Wistar rats were divided into the following 3 groups randomly: the 1-mL EF group, the 0.5-mL EF group, and the control group. The tissue expansion was carried out twice a week to maintain the capsule pressure at 60 mm Hg. After 4 weeks, inflation volume and histological changes, which includes collagen content, cell proliferation, and capillary density, were observed to evaluate the effect of EF on tissue expansion. RESULTS: Mechanical emulsification effectively destroyed the mature adipocytes in adipose tissue. The proportion of MSCs population in the EF fragments was 12.40 ± 0.86%. After expansion, the inflation volume and the levels of collagen deposition, cell proliferation, and capillary density of the expanded tissue in the 1-mL EF group were significantly higher than that in the 0.5-mL EF group and the control group (P < 0.05). However, all these regenerative indicators in the 0.5-mL EF group showed no statistical difference from the control group (P > 0.05). The thickness of epidermal and dermal layers showed no significant difference among the 3 groups (P > 0.05). CONCLUSIONS: Our findings suggested that EF grafting can be used as a new alternative to increase tissue expansion efficiency.
