The experimental study of the effect of ASCs on the skin expansion rate in rabbit

Objective To explore the effect of adipose-derived stem cells (ASCs) on the skin expansion rate in rabbit. Methods The rabbit ASCs were isolated from fat tissue and cultured in vitro. The ADSCs were identified by cell immunofluorescence and marked by Edu staining. 20 new Zealand rabbits were randomly divided into experimental(n=10) and control group(n=10). An area of 1.5 cm×1.5 cm on the one side back of each rabbit was tattooed and one 30 ml round expander was implanted subcutaneously. ASCs suspension(1 ml) was injected subcutaneously in the experimental group, while serum free DMEM medium(1 ml) in control group. The expansion was proceeded regularly under constant pressure for 4 weeks. The expanded tattooed square area was measured on the 7th, 14th, 28th day and analyzed statistically. The expanded skin was harvested for histological study. Immunohistochemical staining was used to detect the expression of vascular endothelial cell marker CD31, and the microvessel density determination. The expression of epidermal growth factor (EGF) and vascular endothelial growth factor(VEGF)was detected by ELISA for skin tissue specificity. Western Blot was used for detection of CK19 in the epidermal cells. Results The expanded skin thickness and expansion rate in experimental group were significant higher than those in control group (P<0.05). Compared with control group, the expression of CK19, CD31 and EGF, VEGF, as well as the microvessel density were all markedly increased in experimental group(P<0.05). Conclusions ASCs can increase the expansion rate of skin tissue by promotion of angiogenesis and tissue regeneration. Key words: Adipose tissue; Stem cells; Soft tissue expansion; Neovascularization