自体乳糜脂肪移植抑制增生性瘢痕的作用及机制

The occurrence of hypertrophic scars is due to the dermal tissue damage caused by the extracellular matrix, especially the abnormal accumulation of collagen and remodeling as the characteristics of skin fibrosis disease. At present, there is still a great challenge for the repair of hypertrophic scar, and it is also a research topic to be solved urgently. Application of fat transplantation as a wide source, good biocompatibility with filler is widely used in repairing defect and promote collagen synthesis, increase dermal thickness, improve microcirculation and so on .The important mechanisium let More researchers pay attention to the mechanism of ADSCs on the treatment of scar, mountainous studies have found that fat adipose derived stem cells (adipose derived stem cells, ADSCs) which are closely related to the anti-fibrosis effect has been confirmed. This project is to establish ADSCs isolation and culture, and the experimental animal model of scar and changes of hypertrophic scar were observed with different concentrations of ADSCs after the injection of scar in nude mice. Moreover, to detect the effect of ADSCs on the activity of fibroblasts and collagen secretion. further exploring the molecular mechanism of the inhibitory effect of ADSCs on hypertrophic scar, Thus, laying a solid theoretical foundation for clinical application.

增生性瘢痕的发生是由于真皮组织损伤导致细胞外基质，尤其是以胶原组织的异常堆积及重塑为特征的皮肤过度纤维化疾病。目前对增生性瘢痕的修复仍是存在巨大挑战性的医学难题之一，也是临床上亟待解决的研究课题。颗粒脂肪移植应用作为一种来源广泛、生物相容性好的自体填充物，在缺损修复中的广泛应用及其在促进胶原合成、增加真皮厚度、改善缺损部位微循环等方面的重要作用，让更多研究者关注其对瘢痕的治疗作用，不少研究发现颗粒脂肪的抗瘢痕作用与脂肪来源干细胞（adipose derived stem cells，ADSCs）密切相关，且其抗纤维化作用在多个研究领域内已被证实，本项目建立人ADSCs分离、培养和鉴定的实验流程，建立瘢痕实验动物模型并观察不同浓度的ADSCs注射裸鼠瘢痕后增生性瘢痕的变化。检测其对瘢痕成纤维细胞的活性及胶原分泌的影响。进一步探索ADSC对增生性瘢痕抑制作用的分子机制，为临床应用奠定坚实的理论

研究背景：.既往研究发现颗粒脂肪的抗瘢痕作用与脂肪来源间充质干细胞（adipose-derived mesenchymal stem cells，ADSCs）密切相关，且其抗纤维化作用在多个研究领域内已被证实。前期我单位应用自体颗粒脂肪技术治疗近200余例瘢痕患者，观察到经治疗后其瘢痕在厚度、色泽等外观方面有较大改善。据此，我们开展了自体乳糜脂肪移植治疗瘢痕的系统的临床疗效观察及吉利研究，以期为乳糜化脂肪治疗增生性瘢痕的相关作用机制研究提供理论依据。.研究内容：.1.乳糜化脂肪制备；.2.人增生性瘢痕裸鼠移植模型制备；.3.乳糜化脂肪来源间充质干细胞生物学特性初步研究；.4.分离培养CFSCs，获得CFSCs-CM，不加胎牛血清的DMEM/F12培养基作为对照组；.5.获取人增生性瘢痕标本，以组织块贴壁法分离培养HSFbs；分别检测细胞增值、细胞划痕检测迁移、细胞凋亡；.6.检测实验组、对照组上清液中Col I（I型胶原蛋白）、Col Ⅲ（Ⅲ型胶原蛋白）、Decorin（核心蛋白聚糖，DN）及α平滑肌肌动蛋白（α-SMA）水平；检测两组中HSFbs的Col I、Col Ⅲ蛋白表达情况。.重要结果和关键数据：.1.瘢痕内注射乳糜化脂肪能够改善胶原堆积等组织学特征；.2.乳糜化脂肪内虽未见脂肪细胞，但有大量ADSCs存在，我们称之为CFSCs；人CFSCs能够高表达间充质干细胞表面标记物，增殖能力强， 且诱导后能够向脂肪组织、骨组织及软骨组织分化；.3.CFSCs-CM可以抑制HSFbs的正常生长增殖，抑制HSFbs迁移，诱导HSFbs细胞凋亡；.4. CFSCs-CM抑制HSFbs中纤维化蛋白因子Col I，Col Ⅲ和α-SMA蛋白的表达，抑制HSFbs分泌表达Col I等细胞外基质蛋白，从而发挥抗纤维化作用。.科学意义：.1.该研究成功构建了人增生性瘢痕移植裸鼠模型，且瘢痕内注射乳糜化脂肪能够改善胶原堆积等组织学特征；.2.乳糜化脂肪富含CFSCs，增殖能力佳，干性极强，呈三系分化；.3.CFSCs-CM能够抑制HSFbs的细胞分裂增殖及迁移能力，影响细胞凋亡；.4. CFSCs-CM抑制HSFbs细胞外基质成分合成；CFSCs-CM可能通过旁分泌途径来发挥抑制HSFbs的作用。