Experimental study of the effect of adipose stromal vascular fraction cells on the survival rate of fat transplantation / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of adipose stromal vascular fraction cells (SVFs) on the survival rate of fat transplantation.</p><p><b>METHODS</b>0. 5 ml autologous fat tissue was mixed with: 1) Di-labeled autologous SVFs ( Group A); 2) Di-labeled autologous adipose-derived stem cells (ASCs) (Group B); 3)Complete DMEM (Group C). And then the mixture was injected randomly under the back skin of 14 rabbits. The transplanted fat tissue in three groups was harvested at 6 months after implantation. Wet weight of fat grafts was measured for macroscopic aspects. After HE staining, blood vessel density, viable adipocytes and fibrous proliferation were counted respectively for histological evaluation. Trace of DiI-labeled ASCs in vivo was detected by fluorescent microscope.</p><p><b>RESULTS</b>The wet weight of fat grafts in group A (291.0 +/- 72.1) mg and group B (269.3 +/- 67.3) mg was significantly higher than that in group C (177.8 +/- 60.0) mg, but the difference between Group A and Group B was not significant. Histological analysis revealed that the fat grafts in group A and B was consisted predominantly of adipose tissue with less fat necrosis and fibrosis, compared with the fat grafts in group C. The grafts in both group A and B had significantly higher capillary density than those in the control group. Part of vascular endothelial cells were observed to origin from ectogenic DiI-labeled SVFs and ASCs.</p><p><b>CONCLUSIONS</b>The autologous isolated SVFs has a similar effect as autologous cultured ASCs to improve the survival rate of fat transplantation. And the former is more practical and safe, indicating a wide clinical application in the future.</p>

Transplantation of adipose tissue-derived stem cells promotes soft tissue wound repair in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the effect of local and intravenous transplantation of adipose tissue-derived stem cells (ADSCs) in promoting soft tissue wound healing in rats.</p><p><b>METHODS</b>ADSCs isolated from the adipose tissues of SD rats were cultured in vitro, and the third-passage cells were identified for their capacity of multipotent differentiation. Eighteen SD rats with 1.8 cm² dorsal full-thickness soft tissue defects (0.5 cm deep) were randomized into 3 groups to receive injection of 3.0×10⁶ DiI-labeled ADSCs via the tail vein, local injection of the cells at the wound site, or injection of saline (control). The wound healing was evaluated on days 3, 7, 11, and 14 postoperatively. On day 24 after the injury, tissue samples at the wound site were collected for fluorescent microscopy and HE staining.</p><p><b>RESULTS</b>The ADSCs obtained were capable of adipogenic, osteogenic, and neurogenic differentiation in vitro. ADSCs transplantation significantly promoted wound healing as compared to the control group. Obvious wound contracture was observed in the local injection group on day 3 and in the intravenous injection group on day 7. Fluorescence microscopy revealed DiI-positive cells in the healing wound, and HE staining showed a greater tissue thickness at the wound in the two ADSCs transplantation groups. Compared to the control group, the two ADSCs transplantation groups showed more gland-like structures and better neovascularization at the wound.</p><p><b>CONCLUSION</b>ADSCs can significantly promote wound healing in rats, and local injection of ADSCs allows more rapid and obvious wound healing than tail veil injection of the stem cells.</p>

Experimental study of the effect of adipose tissue derived stem cells on the survival rate of free fat transplantation / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the feasibility of using adipose tissue derived stem cells (ASCs) to promote neovascularization and survival rate of free fat transplantation.</p><p><b>METHODS</b>ASCs were isolated from aspirates from human liposuction and cultured in vitro. The cells were incubated in adipogenic, osteogenic, and chondrogenic medium for 2-4 weeks to induce adipogenesis, osteogenesis and chondrogenesis, respectively. ASCs were labelled by DiI. ASCs (A group), Insulin (B group), Medium (C group) were respectively mixed with free fat graft from aspirates. The mixtures were injected subcutaneously at the three random points on the back of eighteen 4- 6-week-old nude mice. Transplanted fat tissue was harvested after 6 months. The grafts were assessed by morphological observation, HE staining and immunohistochemistry.</p><p><b>RESULTS</b>ASCs can be easily harvested from liposuction aspirates and differentiate into adipogenic, osteogenic, chondrogenic lineages. The wet weight of transplanted fat tissue in ASCs group was (165.97 +/- 5.51) mg, significantly higher than that in the insulin group (93.42 +/- 5.12) mg and control group (67.64 +/- 5.09) mg (P = 0.000). The rate of fibrosis and steatonecrosis in ASCs group was( 152.2 +/- 9.8)/10HF, significantly lower than that in the Insulin group (743.9 +/- 20.4)/10HF and control group (892.2 +/- 16.5)/10HF (P = 0.000). DiI labelled ASCs were found between adipocytes and in the connective tissue in free transplanted fat tissue, and some of these cells were immunopositive for antihuman CD31 and FITC, suggesting differentiation into vascular endothelial cells.</p><p><b>CONCLUSIONS</b>ASCs can differentiate into vascular endothelial cells and contribute to angiogenesis in free transplanted fat tissue. ASCs can increase the survival rate and decrease the rate of fibrosis and steatonecrosis of free transplanted fat tissue. These findings suggest that ASCs-assisted transplantation may be an ideal cell therapy.</p>