缺氧诱导因子1α基因转染脂肪干细胞与自体脂肪移植

Hypoxia-inducible factor-1α gene transfected adipose-derived stem cells promote the survival of autologous fat grafts

背景:自体颗粒脂肪组织作为理想的填充材料用于美容与重建修复领域,但因其移植后组织大量被吸收,严重影响了远期效果。目的:观察缺氧诱导因子1α基因转染脂肪干细胞对自体移植脂肪组织存活率的影响。方法:取健康成年人吸脂术后的脂肪组织分离脂肪干细胞并行原代及传代培养,传至第3代,调整细胞浓度为1×109L-1,经缺氧诱导因子1α基因转染后调整细胞浓度为1×1011L-1备移植时使用;同时选用同一抽脂术后的脂肪组织颗粒并进行纯化,利用纤维蛋白胶的物理特性制备不同成分脂肪组织复合移植物,在20只裸鼠背部皮下随机分离3个腔隙,实验分为3组:基因修饰组移植经缺氧诱导因子1α基因修饰的脂肪干细胞+脂肪组织+纤维蛋白胶;基因未修饰组移植单纯脂肪干细胞+脂肪组织+纤维蛋白;生理盐水组移植生理盐水+脂肪组织+纤维蛋白。结果与结论:移植后3个月和6个月,各组移植物血管密度比较,基因修饰组>基因未修饰组>生理盐水组,组间比较差异有显著性意义(P<0.05);各组移植物脂肪细胞纤维坏死率比较,基因修饰组<基因未修饰组<生理盐水组,组间比较差异有显著性意义(P<0.05);各组移植物脂肪质量保持率比较,基因修饰组>基因未修饰组>生理盐水组,组间比较差异有显著性意义(P<0.05)。结果证实,缺氧诱导因子1α基因转染脂肪干细胞可促进移植脂肪组织局部的血管再生,促进脂肪细胞的成活,增加脂肪组织的质量保持率,减少脂肪移植术后的纤维坏死程度。

BACKGROUND： Autologous fat is an ideal filling material in aesthetic and reconstructive surgery. However, the long-term effects are poor because much tissue is absorbed after grafting. OBJECTIVE： To investigate the effects of hypoxia-inducible factor-1α gene transfected adipose-derived stem cells on survival of autologous fat grafts.METHODS： Adipose-derived stem cells were isolated from the subcutaneous adipose tissue of healthy adults after liposuction, primary cultured and sub-cultured. Passage 3 adipose-derived stem cells at a density of 1× 109 cells/L were transfected with hypoxia-inducible factor-1α gene. The cells were then adjusted to 1×1011 cells/L. Simultaneously, autologous fat from the same liposuction was selected and purified. The grafts were made according to physiological characteristics of fibrin glue. Three groups were designated. In the gene-modified group, hypoxia-inducible factor-1α gene-modified adipose-derived stem cells, autologous fat＋fibrin glue were transplanted into the back of nude mice. In the non-gene-modified group, adipose-derived stem cells＋autologous fat＋fibrin glue were transplanted in the identical region. In the saline group, physiological saline＋autologous fat＋ fibrin glue were transplanted. RESULTS AND CONCLUSION： At 3 and 6 months after transplantation, the vascular density in the graft was highest in the gene-modified group, followed by non-gene-modified group, and lastly the saline group and there was significant difference between groups （P 〈 0.05）. Fiber necrosis rate of adipose-derived stem cells was lowest in the gene-modified group, followed by non-gene-modified group, and lastly the saline group and there was significant difference between groups （P 〈 0.05）. Fat maintenance rate was highest in the gene-modified group, followed by non-gene-modified group, and lastly the saline group and there was significant difference between groups （P 〈 0.05）. These findings suggest that hypoxia-inducible factor-1α gene transfected adipose-derived stem cells can accelerate the vascularization in the local fat graft transplanted, promote the survival of adipose cells, increase the mass maintenance rate of fat graft and lower the fibrosis necrosis degree after fat grafting.