From the Department of Plastic Surgery, Hand Surgery-Burn Center, Medical Faculty, RWTH Aachen University.
Plast Reconstr Surg. 2018 Jul;142(1):99-109. doi: 10.1097/PRS.0000000000004495.
Adipose-derived stem cells, endothelial progenitor cells, and soluble factors jointly contribute to the regenerative effect of fat grafts. Nanofat grafting emulsifies the lipoaspirate and increases the progenitor cell yield. In the present study, the authors evaluated their extended nanofat grafting method that includes two additional centrifugation steps and results in a lipoaspirate of low volume that they termed "lipoconcentrate." Furthermore, the authors investigated the oily fractions after centrifugation for their regenerative potential.
Lipoaspirates of 20 healthy patients were processed by emulsification and/or centrifugation. Six groups were created: native (not emulsified) fat, 1× centrifuged native fat, 2× centrifuged native fat, nanofat (emulsified), 1× centrifuged nanofat, and lipoconcentrate (i.e., 2× centrifuged nanofat). The oily phases after the centrifugation steps were collected. Progenitor cells and basic fibroblast growth factor, insulin-like growth factor 1, matrix metalloproteinase-9, platelet-derived growth factor-BB, and vascular endothelial growth factor-A levels were measured by flow cytometry and immunoassays.
Lipoconcentrate contained significantly higher numbers of adipose-derived stem cells and endothelial progenitor cells per gram compared with all other fractions. No difference of all five soluble factors between groups was found. The oily phases after centrifugation showed no or very few adipose-derived stem cells and endothelial progenitor cells, and no or very low levels of soluble factors.
Centrifugation of emulsified lipoaspirates increases the progenitor cell count in the lipoaspirate. The oily phase after centrifugation of lipoaspirates may be disposable because of the minuscule content of progenitor cells and soluble factors.
脂肪来源的干细胞、内皮祖细胞和可溶性因子共同促成了脂肪移植物的再生效果。纳米脂肪移植使脂肪抽吸物乳化并增加祖细胞产量。在本研究中，作者评估了他们扩展的纳米脂肪移植方法，该方法包括两个额外的离心步骤，产生了低体积的脂肪抽吸物，他们称之为“脂肪浓缩物”。此外，作者研究了离心后的油性部分的再生潜力。
对 20 名健康患者的脂肪抽吸物进行乳化和/或离心处理。创建了六个组：未乳化的天然脂肪、1 次离心的天然脂肪、2 次离心的天然脂肪、纳米脂肪（乳化）、1 次离心的纳米脂肪和脂肪浓缩物（即 2 次离心的纳米脂肪）。收集离心步骤后的油性相。通过流式细胞术和免疫测定测量祖细胞和碱性成纤维细胞生长因子、胰岛素样生长因子 1、基质金属蛋白酶 9、血小板衍生生长因子-BB 和血管内皮生长因子-A 的水平。
与所有其他部分相比，脂肪浓缩物每克所含的脂肪来源干细胞和内皮祖细胞数量明显更高。未发现各组之间所有五种可溶性因子的差异。离心后的油性相显示几乎没有或很少有脂肪来源的干细胞和内皮祖细胞，以及很少或非常低水平的可溶性因子。
乳化脂肪抽吸物的离心增加了脂肪抽吸物中的祖细胞计数。由于油性相中祖细胞和可溶性因子的含量极少，离心后的油性相可能是一次性的。
