不同脂肪衍生物的体外活力及移植后转归

Viability of different fat derivatives in vitro and the outcome after transplantation

背景:自体脂肪是修复软组织缺损的理想填充材料,然而移植后脂肪组织的长期存活率具有不确定性,探索脂肪组织结构完整性对脂肪移植后存活的影响,可以为提高脂肪移植临床效果提供理论依据。目的:探讨不同脂肪衍生物离体后的活力差异及移植后的转归情况。方法:将吸脂术后获取的脂肪组织制备成4种脂肪衍生物:大颗粒脂肪、中颗粒脂肪、小颗粒脂肪和脂肪胶,比较脂肪获取率及组织学结构完整性,分离获取的脂肪干细胞含量、活力及迁移能力。将4组脂肪衍生物分别随机注射到裸鼠背部,移植后1,12周进行移植物存活率分析、组织结构观察、CD31免疫组织化学染色。结果与结论:①大、中、小颗粒脂肪和脂肪胶体积获取率依次为(71.43±2.87)%,(57.14±3.11)%,(45.72±3.97)%,(11.30±2.33)%,大颗粒脂肪组织学结构最完整,其次为中、小颗粒组,脂肪胶组织结构基本被完全破坏;②大、中、小颗粒脂肪和脂肪胶获取脂肪干细胞的含量依次为(5.03±0.56)×10^(7) L^(-1),(3.77±0.46)×10^(7) L^(-1),(2.01±0.64)×10^(7) L^(-1),(14.84±1.09)×10^(7) L^(-1),差异有显著性意义(P<0.05);③大颗粒脂肪组脂肪干细胞的增殖能力最好,其次为中、小颗粒组,脂肪胶组增殖能力最差;④大颗粒脂肪组脂肪干细胞迁移能力最好,其次中颗粒组,而小颗粒组和脂肪胶组脂肪干细胞迁移能力较差;⑤脂肪移植后脂肪胶组体积保留率最高,其次为大颗粒脂肪组,而小颗粒脂肪组最差;⑥脂肪移植12周时大颗粒脂肪组脂肪细胞部分破坏,中、小颗粒脂肪组脂肪细胞大量破坏,部分囊泡形成,脂肪胶组可见大量成熟脂肪细胞形成;⑦移植12周时大颗粒脂肪组、脂肪胶组血管形成多于中颗粒脂肪组,小颗粒脂肪组最少,差异有显著性意义(P<0.05);大颗粒脂肪组、脂肪胶组间比较差异无显著性意义(P>0.05);⑧结果表明,脂肪组织结构完整性会影响脂肪干细胞产量、活力和移植后脂肪组织存活率。根据不同脂肪衍生物的特点做出合适的选择,以获得最佳的填充效果。

BACKGROUND:Autologous fat is an ideal filler that repairs soft tissue defects,but the long-term survival rate of adipose tissue after transplantation has uncertainty.We explored the effect of adipose tissue structure on the survival of fat transplantation,providing theoretical basis for improving the clinical effect of fat transplantation.OBJECTIVE:To investigate the viability of different fat derivatives in vitro and the outcome after transplantation.METHODS:The adipose tissue obtained after liposuction was prepared into four kinds of adipose derivatives:large granular adipose tissue,medium granular adipose tissue,small granular adipose tissue and stromal vascular fraction gel.Fat acquisition rate and histological structural integrity,content,activity and migration ability of adipose-derived stem cells were compared.Four groups of adipose derivatives were randomly injected into the back of nude mice.The survival rate of the grafts,tissue structure observation and CD31 immunohistochemical staining were performed 1 and 12 weeks after transplantation.RESULTS AND CONCLUSION:(1)The volume acquisition rates of large,medium,small granular fat and stromal vascular fraction gel were(71.43±2.87)%,(57.14±3.11)%,(45.72±3.97)%,and(11.30±2.33)%,respectively.The fat histological structure of the large particles was the most complete,followed by the medium and small granular fat groups,and the tissue structure of stromal vascular fraction gel was basically completely destroyed.(2)The contents of adipose stem cells obtained from large,medium,small granular fat and stromal vascular fraction gel were(5.03±0.56)×10^(7) L^(-1),(3.77±0.46)×10^(7) L^(-1),(2.01±0.64)×10^(7) L^(-1),and(14.84±1.09)×10^(7) L^(-1),respectively,with significant differences(P<0.05).(3)The proliferation ability of adipose stem cells in large granular fat group was the best,followed by medium and small granular fat groups;the proliferation ability of stromal vascular fraction gel group was the worst.(4)The migration ability of adipose stem cells in large granular fat group was the best,followed by medium granular fat group,while that in the small granular fat group and stromal vascular fraction gel group was poor.(5)After transplantation,the volume retention rate of stromal vascular fraction gel group was the highest,followed by large granular fat group,while small granular fat group was the worst.(6)After 12 weeks of fat transplantation,fat cells in large granular fat group were partially destroyed;cells in medium granular fat group and small granular fat group were largely destroyed and some vesicles were formed;a large number of mature fat cells were formed in stromal vascular fraction gel group.(7)At 12 weeks after transplantation,the formation of blood vessels in large granular fat group and stromal vascular fraction gel group was more than that in medium granular fat group,while small granular fat group was the least,with significant differences(P<0.05).There was no significant difference between the large granular fat group and stromal vascular fraction gel group(P>0.05).(8)Results show that structural integrity of adipose tissue affects adipose stem cell production,vitality and adipose tissue survival rate after transplantation.Suitable options are made according to the characteristics of different fat derivatives to achieve the best filling effect.