生长分化因子5诱导人骨髓间充质干细胞微团成软骨分化的研究

[目的]探讨应用生长分化因子5(growth differentiation factor 5,GDF-5)诱导人骨髓间充质干细胞(human bone marrow mesenchymal stem cells,hMSCs)微团成软骨分化的可行性及效果。[方法]体外分离培养hMSCs,取第3代细胞实验。将hMSCs分别用无血清H-DMEM和含10、20、50、100 ng/ml GDF-5的软骨诱导液(chondrogenic medium,CM)诱导,显微镜下观察细胞形态变化,MTT法检测各组细胞的增殖情况。诱导2周后重悬细胞,以5×106/ml的细胞密度离心构建微团,继续诱导2周。RT-PCR检测两组细胞Ⅱ型胶原mRNA的表达。免疫组化、甲苯胺蓝染色检测Ⅱ型胶原和蛋白多糖表达。[结果]hMSCs呈梭形、漩涡状生长。100 ng/ml GDF-5诱导的hMSCs呈圆形或多角形。五组微团分别由无血清H-DMEM、含10,20,50,100 ng/ml GDF-5的软骨诱导液诱导2周后,除H-DMEM组无Ⅱ型胶原mRNA、Ⅱ型胶原蛋白和蛋白多糖的表达外,其他各组Ⅱ型胶原mRNA、Ⅱ型胶原蛋白和蛋白多糖的表达呈...     

生长分化因子5诱导兔脂肪干细胞成软骨细胞分化的实验研究

目的 探讨应用生长分化因子5(growth differentiation factor 5,GDF-5)诱导脂肪干细胞(adipose-deftved stern cells,ADSCs)成软骨细胞分化的可能性及效果. 方法 3月龄清洁级健康日本大耳白兔6只,雌雄不限,体重2～3 kg.取兔皮下脂肪4～6 Ml,采用胶原酶消化离心贴壁培养法培养ADSCs,取第3代细胞进行实验.波形蛋白免疫组织化学和CD44、CD49d、CDl06免疫荧光染色鉴定ADSCs.调整细胞密度为1×106个/Ml,分别用普通细胞培养液以及含0、10、100 ng/Ml GDF.5的软骨细胞诱导液诱导培养.倒置相差显微镜观察细胞形态变化;MTT法检测细胞增殖情况;RT-PCR检测诱导细胞Col Ⅱ和蛋白多糖Mrna的表达;免疫组织化学、阿利新蓝染色、甲苯胺蓝染色和Western blot法检测诱导细胞Col Ⅱ和蛋白多糖表达. 结果 ADSCs呈小圆形、梭形、多角形分布,表面抗原标志CD44、CD49d呈阳性表达,CD106和波形蛋白呈阴性表达.100 ng/Ml GDF-5诱导的ADSCs呈圆形或类圆形,且细胞增殖旺盛.普通培养液和0、10、100 ng/Ml GDF.5成软骨细胞诱导培养后7 d,Col Ⅱ、蛋白多糖Mrna表达均呈浓度依赖性增加,除0、10 ng/Ml GDF-5两组间差异无统计学意义(P>0.05)外,其余各组差异均有统计学意义(P<0.05):100 ng/Ml GDF.5诱导培养14 d,Col Ⅱ、蛋白多糖Mrna以及蛋白表达达高峰,阿利新蓝、甲苯胺蓝染色以及Col Ⅱ免疫组织化学染色均呈阳性. 结论 经一定浓度的GDF-5诱导的ADSCs,Col Ⅱ和蛋白多糖表达明显增加,具有软骨细胞的部分生物学功能.     

不同细胞接种密度体外构建“自组装”工程化软骨的实验研究

[目的]探究以人骨髓间充质干细胞(humanbonemarrowmesenchymalstemcells,hMSCs)为种子细胞体外构建“自组装”工程化软骨对应的合理细胞接种密度.[方法]体外分离与培养hMSCs.用含100ng/ml生长分化因子5(growthdifferentiationfactor5,GDF-5)的软骨诱导液(chondrogenicmedium,CM)定向诱导培养第3代hMSCs,诱导3周后重悬细胞,分别以A组2.5×106/ml,B组5×106/ml,C组1x107/ml,D组2×107/ml四种细胞密度接种于2％琼脂糖包被的24孔板,每组设5个复孔.自组装培养3周后,对标本进行大体观察、组织学及免疫组化检测并进行生化分析,比较不同组标本的软骨生物学特性的差异.[结果]“自组装”培养3周后,各组都形成了软骨样组织团块,团块直径与湿重随细胞接种密度而增加.Bem评分结果显示C、D两组明显高于A、B两组(P＜0.05),且C组与D组间差异无统计学意义,Ⅱ型胶原免疫组化染色检测到C组与D组细胞外基质内有较强的阳性信号弥漫分布,蛋白多糖(GAG)含量C、D两组亦明显高于A、B两组(P＜0.05),且C组与D组间差异无统计学意义.[结论]在一定细胞接种密度范围内,“自组装”工程化软骨的生物学特性呈密度依赖性增加.以1×107/ml接种时,可以获得具有良好生物学特性的“自组装”工程化软骨.     

猪骨髓间质干细胞分离培养及向成软骨细胞表型诱导分化的实验研究

目的建立猪骨髓间质干细胞(bone marrow mesenchymal stem cells,BMMSCs)体外分离培养和在特定诱导液作用下向成软骨细胞表型转化,为其作为组织工程化软骨的种子细胞提供实验基础。方法取猪的胸骨骨髓6~8ml,经密度梯度离心法得到骨髓单个核细胞,在低糖改良Eagle's细胞培养基(Dulbecco's modified Eagle's medium,DMEM)培养2周,将其分为两组,对照组应用高糖DMEM无血清完全培养基培养;实验组在对照组培养基基础上加入转化生长因子β1(transforming growth factor-β1,TGF-β1),在显微镜下观察细胞形态,第7,14d时用免疫组织化学法检测型胶原分泌。结果诱导早期两组细胞形态变化不明显,3d后实验组MSCs由纤维样梭形逐渐向多角形、多边形转变;实验组第7,14d型胶原免疫组织化学阳性,对照组为阴性。结论体外培养猪的BMMSCs生长稳定,传代后仍保持未分化状态,具有分化为软骨的潜能,为基础研究和组织工程提供了一个理想的种子细胞来源。     

成人骨髓间充质干细胞体外诱导分化为软骨细胞的实验研究

目的研究体外三维培养条件下,成人骨髓间充质干细胞(BMSCs)定向分化软骨细胞可行性。方法用密度梯度离心法分离纯化BMSCs,并传代扩增后,用离心三维培养法在软骨诱导剂下进行诱导培养,以常规培养液培养的BMSCs作为阴性对照,于诱导培养第21天取出标本行苏木精-伊红染色、甲苯胺蓝染色、s-100蛋白免疫组织化学检测。结果BMSCs经21d的离心三维诱导培养后,培养管出现软骨外观组织块,组织切片甲苯胺蓝染色呈明显异染,s-100蛋白免疫细胞化学检测阳性。对照组阴性。结论成人BMSCs在三维培养条件下可成功诱导分化为软骨细胞。     

生长分化因子-5诱导小鼠骨髓基质干细胞向软骨分化过程中对缝隙连接蛋白43表达的影响

目的探讨生长分化因子-5(GDF-5)在小鼠骨髓基质干细胞(BMSCs)向软骨分化过程中对缝隙连接蛋白43(Cx43)表达的影响。方法体外培养小鼠BMSCs,贴壁细胞传代,取第3代细胞,加入地塞米松、VitC、胰岛素和GDF-5诱导培养,72 h后免疫细胞化学和阿尔辛蓝染色分别检测软骨细胞特异性Ⅱ型胶原和蛋白多糖的表达；在诱导24、48和72 h后进行如下检测：MTT法测定GDF-5对小鼠BMSCs增殖的影响；RT-PCR、Western blotting和免疫细胞化学法检测GDF-5对Cx43蛋白表达的影响。结果MTT结果显示不同时间GDF-5对小鼠BMSCs的增殖无影响；RT-PCR、Western blotting和免疫细胞化学结果表明诱导后不同时间均有Cx43 mRNA和蛋白的表达；诱导72 h免疫细胞化学显示有Ⅱ型胶原蛋白的表达,阿尔辛蓝染色阳性,有蛋白多糖基质的分泌。结论GDF-5可以通过上调缝隙连接蛋白Cx43的表达来促进小鼠BM- SCs向软骨方向的分化。     

滚压载荷生物反应器促进兔骨髓间充质干细胞向软骨细胞分化的研究

[目的]观察滚压载荷生物反应器对BMSCs-琼脂糖复合体中BMSCs向软骨细胞诱导分化的作用。[方法]分离新西兰兔BMSCs,培养至第3代后与低熔点琼脂糖复合成凝胶块并在自制的模具中形成直径为4 mm、高4 mm的圆柱形胶块。将样本分为TGF-β1+力学组、TGF-β1组、力学组和对照组。在第7、14、21 d时去各组标本进行实时定量PCR、GAG含量检测以及组织学染色。[结果]TGF-β1+力学组II型胶原基因表达在第7、14、21 d 3个时间点随时间的推移逐渐增强,并在第21 d时显著增强。TGF-β1+力学组蛋白聚糖基因在第21 d时也较对照组显著增强并且高于其他两组。对照组的II型胶原和蛋白聚糖基因在3个时间点均见明显增强。TGF-β1+力学组GAG含量在3个时间点均明显升高(P<0.05)并且均高于其余三组。TGF-β1+力学组标本甲苯胺蓝染色较其余各组明显蓝染,并有软骨陷窝样结构。[结论]滚压载荷生物反应器可以有效促进BMSCs-琼脂糖复合体中BMSCs向软骨细胞诱导分化。在结合TGF-β1后这种促进作用更加明显。     

骨髓间质干细胞向软骨细胞表型定向诱导分化的实验研究

目的 研究体外培养的猪骨髓间质干细胞（Bone Marrow Stem Cells,MSCs)在特定培养液作用下向软骨细胞表型转化，探讨其作为组织工程化软骨的种子细胞的可行性。方法 取成年崇明长枫杂交猪髂骨骨髓5ml，在低糖DMEM完全培养液培养2周，传代后以高糖DMEM无血清特定培养液诱导（含胰岛素2mg/L、转铁蛋白3mg/L、丙酮酸100mg/L、地塞米松10^-7mol/L、TGF－β1 10ng/ml)，在相关显微镜和电镜下进行观察，免疫组化检测Ⅱ型胶原分泌，原位杂交检测Ⅱ型胶原mRNA表达。结果 细胞形态由成纤维样梭形向多角形、多边形转变，透视电镜观察见大量扩张粗面内质网、高尔基体、线粒体。诱导培养后第7，14dⅡ型胶原免疫组化阳性，同时原位杂交检测Ⅱ型胶原mRNA表达呈阳性。结论 MSCs在特定培养液诱导下能向软骨细胞表型转化，并能分泌软膏特异性基质，有可能成为软骨组织工程较理想的种子细胞来源的应用前景。     

不同状态软骨细胞在共培养系统下对BMSCs向软骨细胞诱导分化作用的研究

[目的]观察不同代次正常软骨细胞和关节炎软骨细胞对琼脂糖-BMSCs向软骨细胞分化的促进作用.[方法]分离新西兰兔BMSCs,正常软骨细胞.制作兔关节炎模型,提取兔关节炎软骨细胞.将BMSCs和低熔点琼脂糖复合成凝胶块,放在自制的六孔板网格架上,构建兔软骨细胞-BMCSs共培养系统.在3、7、14 d取各组琼脂精BMSCs凝胶块进行实时定量PCR、GAG含量检测.[结果]兔关节炎模型制作成功,关节面色泽较灰暗,关节软骨粗糙.Normal PO-BMSCs组的Ⅱ型胶原基因表达明显增强,Normal P3-BMSCs组Ⅰ、Ⅱ型胶原及蛋白聚糖基因表达均未见明显增强,OA PO-BMSCs组蛋白聚糖基因表达明显增强,OA P3-BMSCs组Ⅰ型胶原基因表达水平在3个时间点均低于对照组.Normal PO-BMSCs组的GAG含量为5.7±0.49μg/mg(湿重),较对照组有明显上升.OA PO BMSCs组GAG含量与对照组相比差异无统计学意义(P＞0.05),其余三组与对照组相比差异均具有统计学意义(P＜0.05).[结论]兔正常PO软骨细胞与兔关节炎PO软骨细胞所分泌的形态发生素能够有效促进BMSCs向软骨细胞分化,而兔正常P3软骨细胞的促分化作用微弱,兔关节炎P3软骨细胞不能促进BMSCs向软骨细胞分化.     

人骨髓间充质干细胞向软骨细胞定向分化的研究

目的探讨体外单层培养中诱导人骨髓间充质干细胞(Human Bone Marrow-derived Mesenchymal Stem Cells,hBMSCs)向软骨细胞定向分化的条件.方法采集志愿者骨髓3例,分离培养BMSCs,流式细胞仪分析表面标志.用含TGF-β1的无血清诱导培养基培养7d后,分别行Ⅱ型胶原免疫组化、原位杂交检测,碱性磷酸酶染色,3H标记的胸腺嘧啶脱氧核苷(3H-TdR)掺入实验检测细胞的增殖情况.结果培养的BMSCs表达CD9,而CD34、CD38、CD45、CD61呈阴性.细胞经诱导培养7d后免疫组化、原位杂交可检测到Ⅱ型胶原的表达,碱性磷酸酶染色呈弱阳性,但细胞3H-TdR掺入量低于对照组(P<0.05).结论BMSCs在特定的诱导下能向软骨细胞方向分化,但在无血清培养基中无法有效的增殖.     

GDF-5在小鼠肢体骨骼发育中的表达及对肢芽细胞影响的研究

目的 :初步观察并探讨生长分化因子 5 (GDF 5 )在小鼠肢体发育过程中的表达及对肢芽细胞软骨分化的影响。方法 :RT PCR法检测小鼠肢体发育过程中GDF 5表达的变化情况 ;MTT法测定不同浓度GDF 5对体外微团培养肢芽细胞增殖率的影响 ;Alcian染色在倒置相差显微镜下观察不同浓度GDF 5对肢芽细胞软骨分化的影响 ,探讨GDF 5影响骨骼系统发育的机理。结果 :RT PCR结果提示GDF 5在胚胎发育的第 12、 13d高表达 ,骨骼系统基本形成之后在孕 14、 15d表达渐下降稳定于一较低水平 ;不同浓度GDF 5对肢芽细胞增殖率影响不同 ,5 0ng/ml浓度组促肢芽细胞增殖作用最强 ;Alcian染色结果显示GDF 5促进肢芽细胞软骨分化的作用呈剂量依赖效应 ,以12 0ng/ml组软骨分化最快 ,软骨结节体积最大 ,10 0ng/ml组软骨结节的数量最多。结论 :GDF 5在肢体发育的不同阶段表达水平不同 ,在骨骼系统形成早期及关节系统形成阶段表达最强 ,主要通过影响肢芽细胞增殖及软骨分化而发挥作用。     

Osteogenic differentiation of adipose-derived stromal cells treated with GDF-5 cultured on a novel three-dimensional sintered microsphere matrix

BACKGROUND CONTEXT: It is well known that under the proper conditions multipotential bone marrow stromal cells are capable of osteogenic differentiation. Recently studies have demonstrated that an analogous subpopulation of cells exist within adipose tissue. Although early studies characterizing these adipose-derived stromal (ADS) cells in culture exist, investigations exploring the characteristics and viability of these cells cultured on a three-dimensional sintered microsphere matrix are absent. PURPOSE: To characterize and investigate the viability of ADS cells cultured on bioengineered three-dimensional sintered microsphere matrices (SMM). STUDY DESIGN: Basic science, laboratory study. PATIENT SAMPLE: Sixty SMM total. Six underwent examination by scanning electron microscopy, 18 for cellular viability, 18 for biochemical assay, and 18 for evaluation by gene expression. OUTCOME MEASURES: The SMM were examined under scanning electron microscopy to evaluate for adherence, migration, and proliferation at 7, 14, and 28 days. Cellular viability was assessed using colorimetric assay for mitochondrial dehydrogenases activity in viable cells (MTS [3-(4,5-dimethylthiazol-2-yl)5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay) at each corresponding time point. Osteoblastic differentiation was determined using biochemical assays for alkaline phosphatase activity and gene expression for alkaline phosphatase (ALP), osteocalcin (OC), and core binding factor alpha-1 (Cbfa1). METHODS: Multipotential ADS cells from adult Sprague Dawley rats were isolated and maintained in media. Sintered microsphere matrices of poly(lactide-co-glycolide) [85:15] were prepared using solvent evaporation technique followed by mechanical sieving and fabricated by heating in metal molds. ADS cells were then seeded on the SMM and cultured in media with growth and differentiation factor-5 (GDF-5). Treated samples and controls were evaluated at 7, 14, and 28 days. Statistical significance was set at p<.05. RESULTS: Multipotential ADS cells were capable of being isolated from adipose tissue. Scanning electron microscopy evaluation revealed cells adherent to the scaffold surface in a monolayer by 7 days. Cytoplasmic extensions were seen linking the cells on adjacent microspheres. Migration and proliferation resulting in extension of the cellular elements into the scaffold was apparent by 14 days. MTS confirmed cell viability within the scaffold throughout the 28-day study. Osteoblastic differentiation was confirmed using biochemical assays for alkaline phosphatase activity and gene expression for ALP, OC, and Cbfa1. CONCLUSIONS: This is the first study to investigate the fate of ADS seeded on a three-dimensional sintered microsphere matrix. The results of this study confirm that ADS cells, when treated with GDF-5, are not only capable of adhering to the bioengineered scaffold, but also remain viable and demonstrated the ability to migrate, proliferate, and subsequently undergo osteogenic differentiation under the conditions described. These early findings support the concept that ADS cells cultured on a SMM may serve as a viable alternative to more traditional methods of bone graft materials.     

糖皮质激素影响间充质干细胞成骨分化的实验研究

目的探讨Notch信号通路在糖皮质激素影响间充质干细胞(mesenchymal stem cells, MSCs)成骨分化过程中的作用。方法培养MSCs,给予糖皮质激素(glucocorticoids, GCs)处理,计算凋亡率,分析细胞凋亡情况;通过real-time PCR方法,检测细胞内Notch信号通路靶基因Hes1和成骨相关基因(ALP,Col1agen1)mRNA的表达;通过Western blot方法检测Notch信号通路靶基因Hes1和成骨相关基因蛋白的表达;应用茜素红染色,检测细胞内成骨钙化作用。结果 GCs处理后,凋亡细胞增加[(80±5.789)vs对照组(60±7.132),P0.05];MSCs成骨分化相关基因ALP、Collagen1mRNA和蛋白表达明显减低,与对照组相比,P0.05;茜素红染色显示GCs组染色强度与对照组相比显著降低(P0.05)。同时,Notch信号通路靶基因Hes1表达明显降低(与对照组相比,P0.05),Notch信号通路表达明显受到抑制。激活Notch信号通路,细胞凋亡百分率降低为72±2.169(与GCs组相比,P0.05);成骨分化基因ALP、Collagen1mRNA和蛋白表达都较GCs组有所提高(P0.05);茜素红染色显示GCs+JAG1组染色强度与GCs组相比明显提高(P0.05)。结论 GCs通过抑制Notch信号通路的表达,进而抑制MSCs的成骨分化。     

A preliminary study comparing the use of allogenic chondrogenic pre‐differentiated and undifferentiated mesenchymal stem cells for the repair of full thickness articular cartilage defects in rabbits

Chondrogenic differentiated mesenchymal stem cells (CMSCs) have been shown to produce superior chondrogenic expression markers in vitro. However, the use of these cells in vivo has not been fully explored. In this study, in vivo assessment of cartilage repair potential between allogenic‐derived chondrogenic pre‐differentiated mesenchymal stem cells and undifferentiated MSCs (MSCs) were compared. Bilateral full thickness cartilage defects were created on the medial femoral condyles of 12 rabbits (n = 12). Rabbits were divided into two groups. In one group, the defects in the right knees were repaired using alginate encapsulated MSCs while in the second group, CMSCs were used. The animals were sacrificed and the repaired and control knees were assessed at 3 and 6 months after implantation. Quantitative analysis was performed by measuring the Glycosaminoglycans (GAGs)/total protein content. The mean Brittberg score was higher in the transplanted knees as compared to the untreated knee at 6 months (p < 0.05). Quantitative analysis of GAGs was consistent with these results. Histological and immunohistochemical analysis demonstrated hyaline‐like cartilage regeneration in the transplanted sites. Significant differences between the histological scores based on O'Driscoll histological grading were observed between contralateral knees at both 3 and 6 months (p < 0.05). No significant differences were observed between the Britberg, O'Driscoll scores, and GAGs/total protein content when comparing defect sites treated with MSC and CMSC (p > 0.05). This study demonstrates that the use of either MSC or CMSC produced superior healing when compared to cartilage defects that were untreated. However, both cells produced comparable treatment outcomes. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1336–1342, 2011     

大鼠骨髓间充质干细胞体外成脂分化能力的实验研究

目的:研究大鼠骨髓间充质干细胞体外成脂分化能力与传代次数的关系。方法:用全骨髓培养法,分离骨髓间充质干细胞,加含有地塞米松、胰岛素、3-异丁基-1甲基黄嘌呤、吲哚美辛诱导剂的培养液进行诱导,诱导第10天进行细胞形态学观察和油红O染色鉴定,并进行光密度值测定。结果:随着传代次数增加,油红O染色细胞计数值与光密度值均下降。结论:大鼠MSCs成脂能力随传代次数增加而降低。     

海藻酸钠-多聚赖氨酸-海藻酸钠微囊对骨髓间充质干细胞生长分化性状的影响

目的探讨运用海藻酸钠-多聚赖氨酸-海藻酸钠(APA)微囊化免疫隔离技术对骨髓间充质干细胞(MSCs)生长分化的影响。方法采用脉冲式高压静电微囊制备仪制备出APA-MSCs微囊复合体,在成囊后第1天和第4天运用荧光素双醋酸酯/溴化乙锭(FDA/EB)染色确定MSCs成活率。采用离心破囊方法破囊,培养并观察破囊后MSCs形态和成骨作用等。结果微囊化后细胞在其内存活率约70%～80%;破囊后的细胞有活跃的增殖能力,经茜素红染色证实具有成骨潜力。结论MSCs在APA微囊内生长良好,保持干细胞特有生长分化,APA微囊可用于对MSCs进行免疫隔离。     

Effect of GDF-5 on ligament healing.

The effects of growth and differentiation factor-5 (GDF-5) on ligament healing were studied using a gap injury model of the medial collateral ligament in rat knee joints. The administration of GDF-5 once at the time of surgery significantly improved the mechanical properties of the femur-ligament-tibia complex. At 3 weeks after surgery, 30 microg of GDF-5 improved the ultimate tensile strength of the complex by 41%, and the stiffness by 60%, compared with the vehicle control (p < 0.05 for both; Fisher's PLSD test). The observation with a transmission electron microscopy revealed that GDF-5 increased the diameter of collagen fibrils in the repair tissue, which was considered to be a possible mechanism for the positive result in the biomechanical testing. Quantitative PCR and in situ hybridization revealed enhanced type I procollagen expression by GDF-5, and the PCR analysis also revealed that the GDF-5 treatment reduced the expression of type III procollagen relative to type I procollagen. The PCR analysis further showed that the expression of decorin and fibromodulin was relatively reduced against type I procollagen by the growth factor, which was considered to be responsible for the increase of collagen fibril diameter in the repair tissue. No adverse effects were observed, and the use of GDF-5 was considered a promising approach to facilitate ligament healing.