连续多次注射富血小板血浆对脂肪移植成活率及移植质量的影响

INFLUENCE OF REPEATEDLY INJECTING PLATELET-RICH PLASMA ON SURVIVAL AND QUALITY OF FAT GRAFTS IN NUDE MICE

目的探讨连续多次注射富血小板血浆(platelet-rich plasma,PRP)对脂肪移植成活率及移植质量的影响,为临床应用提供实验依据。方法取接受吸脂手术的1名25岁健康女性自愿捐赠的大腿后外侧区脂肪,采用静置法纯化脂肪颗粒;抽取其外周静脉血,经两次200×g离心10 min收集PRP;将PRP与10%CaCl2溶液以10∶1混合。选取5周龄雌性裸鼠24只,体重(20±3)g,随机分为实验组与对照组(n=12)。实验组于裸鼠左、右侧背部皮下各注射脂肪颗粒与PRP(10∶2)混合物0.8 mL,对照组注射相同剂量脂肪颗粒与生理盐水(10∶2)混合物。在首次移植后5、10 d,两组再次分别注射PRP与生理盐水0.14 mL。移植后观察裸鼠存活情况;于首次移植后15、30、90、180 d,两组取标本进行大体观察,测定组织块重量与体积;组织学观察组织与细胞形态特征,计算坏死面积比与微血管计数。结果裸鼠均成活至实验完成,两组移植部位均未出现感染及破溃。各时间点实验组组织块表面血管生成以及横切面液化、坏死情况均好于对照组。首次移植后15、30、90 d实验组组织块重量及体积均显著大于对照组(P<0.05),180 d时两组组织块重量及体积相似(P>0.05)。组织学观察示实验组各时间点脂肪细胞形态结构均清晰,中心区空泡逐渐增大,无明显坏死物质及钙化发生;对照组脂肪细胞形态结构逐渐紊乱,且出现大量坏死物质,钙化明显。实验组15、180 d时坏死面积比均小于对照组,微血管计数均多于对照组,差异均有统计学意义(P<0.05)。结论 180 d内连续多次注射PRP辅助脂肪移植能促进脂肪成活并提高移植质量。

Objective To study the effect of platelet-rich plasma （PRP） on the survival and quality of fat grafts in the nude mice so as to provide a method and the experimental basis for clinical practice. Methods Fat tissue was harvested from the lateral thigh of a 25-year-old healthy woman and the fat was purified by using saline. The venous blood was taken from the same donor. PRP was prepared by centrifugation （200 x g for 10 minutes twice） and activated by 10% calcium chloride （10 ： 1）. Then 24 female nude mice [weighing （20 ＋ 3） g, 5-week-old] were allocated randomly to the experimental group and the control group （12 mice per group）. Each subcutaneous layer of two sides of the back （experimental group） was infiltrated with 0.8 mL fat tissue-activated PRP mixtures （10 ： 2）; the control group was infiltrated with 0.8 mL fat tissue-saline mixtures （10 ： 2）; 0.14 mL activated PRP and 0.14 mL saline were injected into the experimental group and the control group respectively at 5 and 10 days after the first operation. At 15, 30, 90, and 180 days after the first operation, the samples were harvested for gross and histological observations. Results All nude mice survived to the end of the experiment. No inflammation and abscess formation of the graft were observed. Experimental group was better than control group in angiogenesis, liquefaction, and necrosis. The grafted fat weight and volume in the experimental group were significantly larger than those in the control group at 15, 30, and 90 days （P 〈 0.05）; but there was no significant difference between the 2 groups at 180 days （P 〉 0.05）. Histological observation showed good morphological and well-distributed adipocytes, increasing vacuoles, few necrosis and calcification in the experimental group; but disordered distribution, obvious necrosis, and calcification in the control group. The necrosis area ratio of the experimental group was significantly lower than that of the control group （P 〈 0.05）, and the number of micro-vessels was significantly higher in the experimental group than in the control group at 15 and 180 days （P 〈 0.05）. Conclusion The method of repeatedly using the PRP within 180 days in assisting fat grafts can obviously improve the survival and quality.