Vascular endothelial growth factor 165-transfected adipose-derived mesenchymal stem cells promote vascularization-assisted fat transplantation.

Objective: To investigate the effect of vascular endothelial growth factor 165 (VEGF165) and adipose-derived mesenchymal stem cells (ASCs) in promoting the survival of fat grafts, and to provide new methods and theoretical evidence for increasing the survival rate of autologous fat particle grafts.

Methods: The VEGF165 gene was recombined with the target fragment, and the recombinant gene was introduced into adenovirus pAdEasy-1 system; the virus was then packaged and the titer was detected. The control group received the same processing. ASCs were cultured and subcultured, and then identified with immunohistochemistry and adipogenic differentiation assay. The subsequent experiments were performed in three groups: the VEGF165 gene-virus group, blank virus group, and control group. After the viral solution was transfected into the ASCs, the viral transfection efficiency was detected using a tracing factor, EGFP. The expression of VEGF165 mRNA and protein in the transfected cells were determined. The proliferation of ASCs in each group was detected with the MTT assay.

Results: (1) Recombinant adenoviral vector was constructed successfully in the two groups and the packaging was identified. The viral titer was 2.0 × 10(8) pfu/ml and 1.9 × 10(8) pfu/ml, which was in line with the requirements of the subsequent transfection experiments. (2) Immunohistochemistry and adipogenic differentiation results showed that the culture of ASCs was successful, and the cultured cells could serve as seed cells in this experiment. (3) The RT-PCR analysis showed that the relative optical density of VEGF165 mRNA expression was 0.76 ± 0.05 in the experimental group, and there were statistically significant differences compared with the values obtained for the other two groups (P < 0.05). (4) The western blot analysis showed that the relative optical density of VEGF165 protein expression in the experimental group was significantly higher than that in the other two groups (P < 0.05). (5) The proliferation of ASCs was significantly enhanced after transfection in the experimental group, relative to the other two groups (P < 0.05). This evidence indicated that VEGF165 significantly promoted the proliferation of ASCs.

Conclusion: After transfection with the VEGF165-adenoviral vector, ASCs demonstrate sustained expression of the target protein and obviously promote the proliferation of ASCs, which lay the foundation for the in vitro experiments on transplantation of VEGF165 combined with ASCs, for the treatment of tissue defects.