背景:在使用扩张的大皮瓣修复大量组织缺损中,并发症的发生率随着面积的扩大而增加。目前,干细胞疗法在解决这个问题上有局限性。我们假设机械预处理后收集的脂肪来源干细胞(ADSC-CM)的条件培养基可以帮助皮肤扩张。
方法:用ADSC-CM培养大鼠主动脉内皮细胞和成纤维细胞,10%,12%,和15%的拉伸力。将10毫升圆柱形软组织扩张器皮下植入36只Sprague-Dawley大鼠的背部。0%和10%拉伸组注射在0%和10%拉伸力下收集的ADSC-CM,分别,对照组不注射。经过3、7、14和30天的扩张,收获扩增的皮肤组织用于染色和qPCR分析。
结果:内皮细胞的管腔形成最好,迁移率最高,在10%拉伸力下收集的ADSC-CM培养后,成纤维细胞分泌的胶原蛋白最多。10%牵张组皮肤扩张率显著增长。经过7天的扩张,扩张区域的血管数量,血管生成相关蛋白血管内皮生长因子的表达,碱性成纤维细胞生长因子,和肝细胞生长因子,10%拉伸组胶原沉积明显增加。
结论:最佳机械力上调ADSCs中的特定旁分泌蛋白,以增加血管生成和胶原分泌,从而促进皮肤再生和扩张。本研究为扩张大型皮瓣提供了一种新的辅助方法。
BACKGROUND: In the repair of massive tissue defects using expanded large skin flaps, the incidence of complications increases with the size of the expanded area. Currently, stem cell therapy has limitations to solve this problem. We hypothesized that conditioned medium of adipose-derived stem cells (ADSC-CM) collected following mechanical pretreatment can assist skin expansion.
METHODS: Rat aortic endothelial cells and fibroblasts were cultured with ADSC-CM collected under 0%, 10%, 12%, and 15% stretching force. Ten-milliliter cylindrical soft tissue expanders were subcutaneously implanted into the backs of 36 Sprague-Dawley rats. The 0% and 10% stretch groups were injected with ADSC-CM collected under 0% and 10% stretching force, respectively, while the control group was not injected. After 3, 7, 14, and 30 days of expansion, expanded skin tissue was harvested for staining and qPCR analyses.
RESULTS: Endothelial cells had the best lumen formation and highest migration rate, and fibroblasts secreted the most collagen upon culture with ADSC-CM collected under 10% stretching force. The skin expansion rate was significantly increased in the 10% stretch group. After 7 days of expansion, the number of blood vessels in the expanded area, expression of the angiogenesis-associated proteins vascular endothelial growth factor, basic fibroblast growth factor, and hepatocyte growth factor, and collagen deposition were significantly increased in the 10% stretch group.
CONCLUSIONS: The optimal mechanical force upregulates specific paracrine proteins in ADSCs to increase angiogenesis and collagen secretion, and thereby promote skin regeneration and expansion. This study provides a new auxiliary method to expand large skin flaps.