人脂肪来源干细胞复合I型胶原支架构建工程化脂肪组织的实验研究

目的 探讨构建组织工程化脂肪组织的可行性,为临床修复软组织缺损寻找一种新方法.方法 以酶消化法从人脂肪抽吸术抽吸物脂质部分获取人脂肪来源干细胞作为种子细胞,并行Dil体外荧光标记,以Ⅰ型胶原支架为载体材料,将细胞成脂诱导后,以1×107/ml细胞密度与支架复合后接种于裸鼠左侧背部皮下,未诱导组不对细胞进行任何诱导,以相同方式接种于裸鼠右侧背部皮下,空白对照组将Ⅰ型胶原空白支架接种于裸鼠颈部正中皮下,每组各6只实验鼠;于第12周取材,通过大体和荧光显微镜观察、湿重测定、组织学检测和油红0染色定性判断体内成脂能力.结果 原代培养的脂肪来源干细胞,经成脂诱导能演变为成熟脂肪细胞,油红0染色阳性.诱导组裸鼠皮下均发现新生组织块,新生物平均湿重为0.020 g,常规病理切片及油红0染色均证实其为成熟脂肪组织,Dil荧光显色阳性证实其为外源性;未诱导组4只裸鼠皮下发现新生组织块,新生物平均湿重为0.014 g,常规病理切片及油红0染色证实其含有部分成熟脂肪组织,Dil荧光显色阳性证实其为外源性.两组新生物湿重比较差异有统计学意义(P<0.01);空白对照组未见新生组织形成.结论 用酶消化法从人脂肪抽吸术抽吸物脂质部分提取的细胞为脂肪组织来源干细胞,该细胞能作为种子细胞经成脂诱导后.与Ⅰ型胶原支架在体内成功构建脂肪组织.     

人脂肪细胞的可塑性

目的 探索体外培养环境下人成熟脂肪细胞的去分化现象,旨在挖掘其作为种子细胞的潜能,为组织工程研究开辟新思路.方法 自成人吸脂术后抽吸物提取成熟脂肪细胞及脂肪组织来源干细胞(adipose-derived stromal cells,ASCs),天花板贴壁培养法诱导成熟脂肪细胞去分化,观察细胞形态变化,获得去分化脂肪细胞(dedifferentiated adipocytes,DA).相同的条件下,MTT比色法比较DA、ASCs活性并绘制细胞生长曲线;流式细胞仪鉴定DA、ASCs表面分子的表达;油红O染色、茜素红染色、阿尔辛蓝染色分别鉴定DA、ASCs成脂分化、成骨、成软骨分化能力.结果 人成熟脂肪细胞在体外培养环境下能去分化为成纤维细胞状DA;MTT比色法测细胞活性:DA、ASCs均有很强的增殖能力,两者差异无统计学意义;流式细胞仪测定:DA、ASCs中HLA-ABC、CD29、CD44均为阳性,CD45、CD34、CD106均为阴性;成脂分化2周,油红O染色可见DA、ASCs内出现红色脂滴;成骨分化2周,茜素红染色可见DA、ASCs内红色钙盐沉积;成软骨分化2周,阿尔辛蓝染色可见DA、ASCs内软骨基质沉积.结论 成熟的脂肪细胞在体外培养条件下可成为DA,DA具有很强的增殖活性,表达部分干细胞特征性表面蛋白,有成骨、成软骨及强大的成脂分化能力,有望成为组织工程优秀的种子细胞.

Abstract：

Objective To explore the dedifferentiation phenomenon of human mature adipocytes cultured in vitro and to discuss the possibility of using dedifferentiation adipocytes ( DA ) as seed cells.Methods Mature adipocytes and ASCs were harvested from human fat aspirates. Mature adipocytes were cultured and induced to DA by ceiling adherent culture method. Cell morphology were observed during the whole process. Viabilities of DA and ASCs were compared by MTT chromatometry and cell growth curves were drawn based on it. Cell surface markers of DA and ASCs were detected by flow cytometry. The adipogenic,osteogenic and chondrogenic ability of DA and ASCs were assessed by oil red O staining,alizarin bordeaux staining and alcian blue staining, respectively. Regults Human mature adipocytes can dedifferentiate into fibroblast-shaped DA. MTT chromatometry assay demonstrated that DA and ASCs both had strong reproductive activity, with no significant difference between them. Flow cytometry assay demonstrated that both DA and ASCs expressed HLA-ABC, CD29 and CD44, while didn't express CD45,CD34 and CD106. After two weeks of adipogenic differentiation, lipid droplets could be displayed by oil red O staining in both DA and ASCs. After two weeks of osteogenic differentiation, calcium salts mineralization in DA and ASCs could be detected by alizarin bordeaux staining. After two weeks of chondrogenic differentiation, matrix of cartilage cells in DA and ASCs could be detected by alcian blue staining. Conclusions Mature adipocytes can be dedifferentiated into DA in vitro. DA has strong reproductive activity, as well as osteogenic, chondrogenic ability and strong adipogenic ability. It expresses some of the stem cell-related cell surface proteins and is a promising seed cell for adipose tissue engineering.     

CD204阴性人脂肪来源细胞体外成软骨潜能的初步研究

目的比较CD204+和CD204-两种人脂肪来源细胞的干细胞特性和体外诱导成软骨的能力。方法分离培养人脂肪来源细胞并进行流式细胞分选,分别获得CD204+和CD204-两种细胞。将这两种细胞培养扩增至第2代,观察其形态学特点;成脂、成骨定向诱导分化,油红O染色、茜素红染色定性;同时将两种细胞进行pellet成软骨诱导分化,比较体外诱导成软骨的能力,并以HE、Safranin O和Ⅱ型胶原免疫组化染色等进行鉴定。结果经流式细胞分选,脂肪来源细胞中CD204表达阳性率约为10%。分选后的CD204+和CD204-细胞均呈成纤维细胞样贴壁生长,但CD204-细胞具有更强的增殖能力。成脂诱导10 d后,两组细胞油红O染色均可见胞浆内有大量红染脂滴,但CD204+细胞具有更强的成脂潜能。成骨诱导2周后,两组细胞茜素红染色均可见钙结节红染,而CD204-细胞具有更强的成骨潜能。同时,细胞pellet成软骨诱导4周后,大体观可见CD204-细胞组pellet形成白色透明样软骨成分,而CD204+细胞组pellet外观微黄。HE和Ⅱ型胶原免疫组化染色均显示CD204-组pellet可见成熟软骨陷窝形成,Safranin O染色显示CD204-组软骨特异性细胞外基质沉积;而CD204+细胞组pellet则呈纤维化改变。结论脂肪组织来源的CD204-细胞具有干细胞的生物学特点,且有良好的成软骨潜能,可以成为软骨组织工程良好的种子细胞来源。     

高成脂脂肪干细胞系的分子克隆筛选

目的 探讨并筛选具备高成脂能力的脂肪干细胞系表面标志、可应用于脂肪组织工程的种子细胞,以提高组织工程化脂肪的构建效率.方法 胶原酶消化人脂肪组织,获得脂肪干细胞,培养扩增后成脂诱导,收集诱导成熟的脂肪细胞,天花板贴壁培养得到去分化脂肪细胞.比较去分化脂肪细胞与人脂肪干细胞的增殖能力,成脂分化能力及表面抗原表达的变化.结果 去分化脂肪细胞与脂肪干细胞的形态和增殖能力相似;去分化脂肪细胞的成脂分化能力高于脂肪干细胞;两种细胞表面抗原的表达大致相同,但去分化脂肪细胞的CD54的阳性表达高于脂肪干细胞.结论 CD54的表达可能与去分化脂肪细胞的高成脂分化能力密切相关,可能是高成脂系干细胞的特异性表面抗原标志.     

人脂肪干细胞的体外培养鉴定及分化特性

目的：在体外从脂肪块中分离出脂肪干细胞（adipose derived stem/stromal cells,ASCs）,对其进行形态观察、干细胞鉴定、增殖和分化能力检测。方法：将腹部取皮术的皮下脂肪利用胶原酶消化法,进行体外分离培养,取第3代的细胞进行细胞爬片HE染色、流式鉴定、MTT、细胞周期检测等,利用成脂和成骨培养液诱导,油红O和茜素红染色鉴定诱导结果。结果：原代培养第1次换液时细胞多呈多角形和短梭形,第3代ASCs细胞爬片HE染色显示形态多为长梭形,呈漩涡状生长;流式鉴定显示：CD29＋,CD31-,CD34-,CD44＋,CD45-,CD49＋,CD106-,CD133-;MTT显示ASCs生长增殖活性强;细胞周期检测结果显示：G1=86.8%,G2=8.77%;成脂诱导后油红O染色阳性,对照组为阴性;成骨诱导后茜素红染色阳性,对照组为阴性。结论：人ASCs具有贴壁生长、多向分化以及干细胞表型等特征,且生长增殖活性强,是一种很有应用前景的间充质干细胞。     

人脂肪组织来源干细胞植入裸鼠的成脂效应

目的 探讨脂肪抽吸术液态部分获取的人脂肪组织来源干细胞(adipose tissue-derivedstem cells,ADSC)植入裸鼠的成脂效应.方法 自人体脂肪抽吸术中液体部分分离、培养和鉴定ADSC,行成脂、骨和软骨分化.植入物分三组:空支架(第1组),人ADSC接种胶原海绵(第2组),经成脂诱导的ADSC接种胶原海绵架(第3组),植入裸鼠皮下.在2和8周时,通过组织观察、HE染色和油红O染色来分析新生组织.结果 抽脂术液态部分能获取大量的ADSC,能分化成脂肪、成骨和软骨细胞.8周时,第1组植入物已降解,第2组和第3组均有脂肪组织形成,但第2组比第3组在形成体积上小、成脂效应差.结论 从脂肪抽吸术液态部分分离和培养的ADSC和胶原支架混合培养能在体内形成脂肪组织,此方法 获得的ADSC多能干细胞可作为脂肪组织工程的种子细胞.     

基质血管成分与体外扩增的脂肪来源干细胞促进移植脂肪成活的对比研究

目的:比较血管基质成分(st romal vascul ar fract i on,SVF)与体外扩增的脂肪来源干细胞(adi pose-deri ved st emcel l s,ASCs)对移植脂肪成活的促进作用。方法:用手术方法切取家兔腹股沟脂肪,进行ASCs体外分离培养;取第3代ASCs分别进行成脂、成骨诱导实验,CD29和CD31流式鉴定;制备SVF,进行CD29和CD31流式鉴定;脂肪移植裸鼠实验分为3组:SVF、ASCs、和空白对照组(DMEM/F12),每组4只裸鼠,沿背部脊柱两侧对称部位4个移植位点,每组共16个注射移植位点,每点0.3ml脂肪颗粒(adi pose granul e,AG)+0.2ml细胞成分;术后4m时取材称重、固定行HE染色观察移植脂肪组织结构,行CD31免疫组化染色观察新生血管及其密度。结果:家兔ASCs体外分离培养成功,为贴壁生长,第3代细胞形态均呈长梭形。成脂诱导实验油红O染色显示形成脂滴,成骨诱导实验茜素红染色显示形成钙化结节。流式鉴定显示SVF:CD29:17.0%,CD31:1.3%;ASCs:CD29:96.2%,CD31:3.8%。SVF、ASCs和空白对照组各组移植脂肪成活量分别为0.2096±0.0024g,0.1798±0.0033g,0.1350±0.0020g,两两比较差异均有统计学意义,P<0.05。HE染色显示SVF组移植脂肪成活较好,组织结构完整,脂滴大小均一,可见脂肪组织中间有丰富的血管存在;ASCs组移植脂肪成活尚可,组织结构尚完整,脂滴大小一般均一,可见脂肪组织中有结缔组织纤维间隔和新生血管形成;空白对照组结缔组织纤维间隔明显增多,脂滴大小不一,有少量较大空泡形成。各组移植脂肪新生血管密度分别32.6±2.1条/mm2,29.3±1.6条/mm2,23.3±1.9条/mm2,两两比较均有统计学意义,P<0.05。结论:新鲜的干细胞成分SVF比体外扩增的ASCs能更好的促进移植脂肪成活。     

脂肪组织来源干细胞提高游离脂肪移植存活率的研究

目的 探讨脂肪组织来源干细胞移植在体内促进游离移植脂肪组织的再血管化,提高移植脂肪组织存活率的可行性.方法 自人体吸脂术中脂质部分分离、培养AScs,行成脂、骨和软骨分化.将ASCs以DiI标记后与人体吸脂术获得的脂肪组织混合移植于18只裸鼠背部,裸鼠背部随机注入3组移植物:ASCs组(A组)、胰岛素组(B组)及培养基对照组(C组).术后6个月观察移植物情况,通过组织观察、HE染色和免疫组化进行分析.结果 抽脂术脂质部分能获取大量的ASCs,能分化成脂肪、成骨和软骨细胞.术后6个月3组移植脂肪的湿重分别为A组(165.97±5.51)mg,B组(93.42±5.12)mg,C组(67.64±5.09)lIIg.A组移植脂肪的存活率高于B、C组(P=0.000).纤维化程度的测定,"网格点计数"3组移植物的点个数分别为A组(152.2±9.8)个/10HF,B组(743.9±20.4)个/10HF,C组(892.2±16.5)个/10HF.A组移植脂肪的纤维化及坏死程度低于B、C组(P=0.000).免疫组化证实:ASCs散在分布于部分脂肪细胞及小叶间隔中,ASCs在体内能够部分转化为血管内皮细胞.结论 脂肪组织来源干细胞移植在体内可促进游离移植脂肪组织的再血管化,提高移植脂肪组织的存活率并改善了移植物的质地.AsCs辅助移植可能是一种较为理想的细胞疗法.     

脂肪组织来源干细胞定向分化脂肪组织的体内外实验研究

目的 分离和培养脂肪组织来源干细胞（ASCs），鉴定其是否具有干细胞表面标志，研究携带GFP基因的ASCs向脂肪组织的体外定向诱导分化能力，同时判断种子细胞ASCs与Ⅰ型胶原支架混合培养后在体内构建组织工程化脂肪组织的可能性。方法 取GFP小鼠腹股沟部脂肪组织，使用酶消化法进行原代培养，流式细胞仪鉴定其表面干细胞标志，细胞传至第3代后使用脂肪分化培养基诱导2周，观察细胞形态及功能变化。将诱导分化后的细胞与支架材料混合培养后12h，将支架材料移植到裸鼠背部皮下，观察新生组织情况，并对新生组织使用HE及油红O染色进行鉴定。结果 原代培养的ASC形态类似于成纤维细胞，具有很强的增殖能力，能持续稳定表达表面干细胞标志。在脂肪分化培养基的作用下，胞浆内脂滴不断聚集，逐渐演变为成熟的脂肪细胞，油红O染色阳性。体内实验中在裸鼠皮下发现了0．5ml的新生组织块，常规病理及油红O染色均证实其为成熟脂肪组织块。结论 脂肪组织来源的干细胞ASC能在体外定向诱导分化为成熟脂肪细胞，且ASC能作用种子细胞与Ⅰ型胶原支架在体内成功构建脂肪组织。     

不同层次脂肪干细胞在裸鼠脂肪移植的比较研究

目的探讨静置后脂肪颗粒提取脂肪干细胞(PLA-ADSC)和静置后下层滤液提取的脂肪干细胞(LAF-ADSC)诱导裸鼠成脂的机制, 为细胞辅助的脂肪颗粒移植提供思路。方法 2019年6月至2021年3月, 于成都八大处医疗美容医院整形外科和成都市第三人民医院医学美容部手术室行正常人体的脂肪抽吸手术, 将通过手术获得的脂肪组织抽吸物静置, 得到上层脂肪颗粒组织进行消化、分离培养PLA-ADSC并鉴定;得到下层液体组织离心后取沉淀物, 沉淀物进行消化、分离培养LAF-ADSC并鉴定;比较PLA-ADSC和LAF-ADSC分化特性及其生长能力。动物实验分实验1组和实验2组, 将基质胶Matrigel移植至裸鼠体内设为对照组, 比较3组裸鼠体内的成脂能力。结果细胞实验结果显示, 静置后脂肪颗粒及下层滤液沉淀物提取细胞均能贴壁生长并顺利传代, 上述两种不同来源细胞均表达CD44、CD73、CD105, 阳性率分别为99.5%、99.99%、99.7%, CD19、CD31、CD45则为阴性表达。成脂诱导分化结果显示, 胞质内有脂滴形成, 细胞油红O染色后可见脂滴呈橘红色。动物实验结果显示, 移植后...     

Cell biological study of cultured cells derived from the fattyoffluid portions of liposuction aspirates]

OBJECTIVE: To explore an approach to isolate and culture the Adipose derived stem cells (ASCs) from the fatty and the fluid portions of liposuction aspirates, and to investigate the growth kinetics, morphology, differentiation capability, cell senescence, surface marker profiles of the ASCs. METHODS: The liposuction aspirates were divided into fatty portion and liquid portion. ASCs were isolated from each portion by collagenase digestion and directly centrifugate and cultured to observe the morphology and biology characters in vitro. Cell activity was studied by MTT chromatometry and analyzed statistically. Cell cycle was detected by flow cytometry. Cells were randomly selected from the 3rd, 4th, 6th, 8th generation cells to dectect senescence of ASCs by acridine orange staining. The cell surface markers were detected by flow cytometry and immunohistochemistry. Adipogenic and osteogenic lineage differentiation of ASCs was assessed by Oil Red O and alizarin bordeaux staining respectively. RESULTS: A large amount of ASCs could be islated and cultured both from the fatty portion and the liquid portion, including PLA cells and LAF cells which had fibroblastic characters with strong viability and proliferative activity. The statistical result indicated that the cell activity of PLA cells and LAF cells was very similar. ASCs from passage 3, 4, 6, 8 didn't show insenecence. CD29, CD44, CD34, which were the markers of mesenchymal stem cells, vWF, CD31, CD105, SMA were all expressed in ASCs. Adipogenic differentiation of ASCs was assessed by Oil Red O staining after 2 weeks. The cells contained many lipid-filled droplets. After 2 weeks' osteogenic induction, cells were positively stained by alizarin Bordeaux. CONCLUSIONS: The method can isolate ASCs by directly centrifugate from the fatty and the fluid portions of human liposuction aspirates. The way of culture is convenient and economical. ASCs isolated from the liquid and fatty portions of liposuction aspirates show identical in cells numbers and quality. LAF cells and PLA cells have similar characters in growth dynamics, morphology, cell senescence, surface marker profiles and differentiation ability, etc. Expression of the cell surface marker of stem cells is also observed in ASCs. ASCs can differentiate into adipose and osteogenesis directionally. The results suggest that the ASCs, which are isolated with minimum intervention, may be the ideal seed cells for adipose tissue engineering in future.     

Secretory Factors From Rat Adipose Tissue Explants Promote Adipogenesis and Angiogenesis

Adipogenic differentiation of adipose‐derived stem cells (ASCs) is known to be affected by many promoting and inhibiting factors, and correlated with surrounding cells and extracellular matrix. However, few studies have evaluated the effect of secreted biological molecules from adipose tissue explants on the growth of ASCs. In this study, ASCs were isolated and the secretory factors from adipose tissue explants (SFAE) were prepared from adipose tissue explants. The multilineage differentiation potential of ASCs was determined using different inductive media. The influence of SFAE on the colony formation and proliferation of ASCs was determined using colony‐forming efficiency assay and Cell Counting Kit‐8 assay, respectively. Real‐time polymerase chain reaction and Western blot were performed to analyze the beneficial effect of SFAE on the adipogenesis and angiogenesis of ASCs. Utilizing gelatin scaffold, the influence of SFAE on ASCs was investigated in vivo. Subsequently, cell/gelatin constructs were cultured in a subcutaneous pocket on a rat dorsum for 2 and 9 weeks, and the resultant samples were histologically evaluated. Results showed that ASCs derived from adipose explants can differentiate along multiple lineages in vitro. Utilizing SFAE, the proliferation and colony‐forming efficiency of ASCs were inhibited, while the expression of adipogenesis markers such as C/EBPβ, PPARγ2, and LPL, as well as angiogenesis factor VEGF‐A were promoted. Moreover, the beneficial effect of SFAE on adipogenesis was revealed in vivo. In conclusion, our results suggested that SFAE has beneficial influence on adipogenesis and angiogenesis both in vitro and in vivo.     

促进脂肪来源间充质干细胞成骨分化的诱导方法研究进展

脂肪来源间充质干细胞(ASCs)是一种多能成体干细胞,因安全、含量丰富、易于获取等优点而有望成为理想的骨组织工程(BTE)种子细胞。然而,相较于骨髓间充质干细胞,ASCs的成骨分化能力有限,往往需要进一步诱导。该文从优化支架、添加生物活性因子或促成骨药物、非编码RNA调控和物理刺激几个方面,对促进ASCs成骨分化的诱导方法的研究进展进行综述,以期为BTE研究提供参考。