脱矿脱细胞骨基质环支架体外构建组织工程化椎间盘纤维环

目的:探计以脱矿脱细胞骨基质环为支架、纤维环细胞为种子细胞体外培养构建组织工程化椎间盘纤维环的可行性.方法:取兔椎间盘纤维环细胞培养,应用甲苯胺蓝染色和Ⅰ型、Ⅱ型胶原免疫组织化学染色进行鉴定.用纤维蛋白凝胶接种技术将兔椎间盘纤维环细胞接种到经脱矿脱细胞制备的骨基质环支架材料上,体外培养3个月.每月取培养的细胞支架复合体进行大体形态、HE染色光镜检查和扫描电镜观察,并用生化方法榆测羟脯氨酸、氨基葡聚糖(GAG)、脱氧核糖核酸(DNA)含量;逆转录聚合酶链反应(RT-PCR)方法检测Ⅰ、Ⅱ型胶原信使核糖核酸(mRNA)表达;免疫组化和蛋白质印迹方法检测Ⅰ、Ⅱ犁胶原蛋白表达.结果:培养的第1代细胞甲苯胺蓝染色呈异染性,Ⅰ型、Ⅱ型胶原免疫组化染色均可见阳性表达,表明培养的第1代细胞具有椎间盘纤维环细胞的表型特点.构建的复合体体外培养1、2、3个月时大体呈白色半透明样环状,有光泽,质韧,具有一定弹性,可扭曲;HE染色光镜下见支架孔洞被红染的组织填充,且空洞内的细胞密度逐渐增加;扫描电镜观察材料表面逐渐被组织填充;Ⅰ型、Ⅱ型胶原免疫组化染色均为阳性;培养2个月时复合体羟脯氨酸、GAG、DNA含量明显高于1个月时(P<0.01),3个月时与2个月时比较无显著性差异(P>0.05).各时间点复合体羟脯氨酸、GAG、DNA含量均低于正常纤维环(P<0.05或<0.01);培养1个月时复合体可检测到Ⅰ、Ⅱ型胶原mRNA和蛋白的表达.2个月时与1个月时比较有显著性差异(P<0.01),3个月时与2个月时比较无显著性差异(P>0.05).结论:以脱矿脱细胞骨基质环为支架、纤维环细胞为种子细胞构建的复合体在体外培养时,细胞能够保持表型特点、逐渐增殖和行使功能,此复合体可被鉴定为类纤维环组织,用其构建组织工程化椎间盘纤维环可行.     

壳聚糖/Ⅰ型胶原复合支架与滑膜成纤维样细胞构建颞下颌关节盘的研究

目的 探讨利用滑膜成纤维样细胞(SFBs)及壳聚糖/Ⅰ型胶原(CS/COL-Ⅰ)复合支架构建颞下颌关节盘软骨的可行性.方法 获取兔颞下颌关节滑膜组织进行SFBs培养,第3～5代SFBs三维培养于通过冷冻干燥法制备的CS/COL-Ⅰ支架材料中7 d,用噻唑蓝(MTT)比色法分别在1、3、5、7 d检测支架材料对细胞增殖的影响.细胞支架复合物在体外经过人重组转化生长因子β1(rhTGF,10μg/L)和碱性成纤维细胞生长因子(bFGF,50 μg/L)诱导后,植入裸鼠体内4、8周后获取标本,进行组织学检测细胞在支架材料上的生长状态及黏多糖(GAGs)形成,免疫组织化学和逆转录-聚合酶链反应(RT-PCR)半定量分析Ⅱ型胶原的表达.结果 支架材料表面及内部均呈多孔隙蜂窝状结构.SFBs在CS/COL-Ⅰ中的增殖要明显高于平板培养(P＜0.05).细胞支架复合物植入裸鼠体内4、8周后,组织学及免疫组织化学半定量分析显示在8周时GAGs(6.900±0.316)和Ⅱ型胶原(0.0952±0.0248)IA/μm2与4周时GAGs(3.600±0.699)和Ⅱ型胶原(0.0411±0.0127)IA/μm2差异有统计学意义(P＜0.05).结论 体外诱导后的SFBs/CS-COL-Ⅰ复合物具有应用于组织工程化颞下颌关节盘构建的可能.     

组织工程软骨体外构建的相关实验研究

目的 探索组织工程软骨体外构建技术体系可行性.方法 种子细胞选用胎儿软骨细胞(口服药物流产胎儿,胎龄3～6个月).酶消化法获得第1代细胞,以50×106/ml浓度均匀接种于经聚乳酸(PLA)包埋聚乙醇酸(PGA)高分子聚合物支架,形成细胞-支架复合体,在体外静态培养.分别于2周、4周、8周进行大体观察、扫描电镜及组织学检测.结果 体外构建的组织工程软骨,随培养时间延长,色泽由2周时的乳白色逐渐呈现半透明,8周时接近正常软骨外观.扫描电镜显示软骨细胞与材料具有良好相容性,培养7天PGA纤维之间有基质沉积.HE染色示2周有大量软骨陷窝形成和均匀嗜碱性基质分泌,Safranin'O染色示基质有酸性蛋白多糖分布,Massons's trichome染色示基质有胶原成分,但含量较少,经免疫组织化学检测为特异Ⅱ型胶原.培养4周胶原成分开始明显增多,软骨陷窝形态接近成熟,8周细胞外基质蛋白多糖和Ⅱ型胶原含量丰富且分布均匀.结论 以成熟软骨细胞为种子细胞,运用组织工程技术在体外能构建出具有正常软骨组织结构特征的人组织工程软骨.     

胰岛素样生长因子-Ⅰ促进体外组织工程软骨形成

目的　探讨胰岛素样生长因子 - (IGF- )体外促进以透明质酸 (HA)为支架材料的组织工程软骨形成的能力。　方法　分离培养人关节软骨细胞 ,分为 3组 :1IGF- 组 :HA支架材料 软骨细胞 IGF- ;2细胞组 :HA支架材料 软骨细胞 ;3对照组 :单纯 HA支架材料。各组在 DMEM中培养 ,3、6周停止培养 ,取组织块通过 HE染色判断培养组织的形态 ,采用甲苯胺蓝染色、 型胶原免疫组织化学及 、 型胶原 RT- PCR判断体外组织形成软骨的能力。　结果　 IGF- 组和细胞组在第 6周均能形成典型的软骨组织陷窝 ,细胞组的陷窝数量明显低于 IGF- 组 ;对照组不能形成软骨组织。 型胶原免疫组织化学示 IGF- 组阳性表达强于细胞组 ;RT- PCR示 IGF- 组的 型前胶原量明显高于细胞组 (P<0 .0 5 ) ,而 型前胶原的表达量明显低于细胞组 (P<0 .0 5 ) ,差异具有统计学意义。　结论　 IGF- 能促进体外构建的组织工程软骨形成 ,并提高其质量。     

聚乳酸-聚羟基乙酸/Ⅰ型胶原复合支架的生物相容性研究

目的观察聚乳酸-聚羟基乙酸(poly-lactide-co-glycolide,PLGA)/Ⅰ型胶原复合支架的生物相容性,探讨其作为组织工程阴道支架的可行性。方法取经多聚赖氨酸包被的PLGA置于含0.25%Ⅰ型胶原的醋酸水溶液,制备PLGA/Ⅰ型胶原复合支架。取10~12周龄雌性SD大鼠阴道组织,采用酶消化法分离培养阴道上皮细胞,取第2代细胞进行实验。取复合支架浸提液培养阴道上皮细胞,观察材料细胞毒性。将阴道上皮细胞与复合支架共培养48 h(实验组),检测细胞黏附率;以单纯PLGA支架接种细胞作为对照组。将细胞-支架复合物埋植至SD大鼠皮下,于2、4、8周取材行HE染色、免疫组织化学染色,观察细胞在支架上生长情况。将细胞-支架复合物移植至6只切除阴道组织的SD大鼠阴道部位,于术后3、6个月观察阴道生长情况,6个月后取阴道组织进行组织学观察。结果大鼠阴道上皮细胞在PLGA/Ⅰ型胶原复合支架材料浸提液中生长、增殖良好,细胞毒性为1级。实验组细胞黏附率为71.8%±9.2%,显著高于对照组的63.4%±5.7%(t=2.195,P=0.005)。阴道上皮细胞能在PLGA/Ⅰ胶原复合支架材料上黏附、生长;大鼠皮下埋植2周后,细胞在支架孔隙内生长增殖,成纤维细胞生长;4周支架材料表面形成1~3层上皮;8周后支架材料部分降解,上皮层次增加,呈极性排列,角蛋白免疫组织化学染色呈阳性。细胞-支架复合物原位移植3个月后,大鼠阴道黏膜呈粉红色,有光泽,支架材料大部分降解;6个月时阴道深约1.2 cm,无明显狭窄,阴道黏膜外观类似正常阴道黏膜,皱襞较少,组织学观察示上皮层与正常阴道无明显区别,基底层可见钉状突起,数量少于正常阴道,角蛋白免疫组织化学染色呈阳性。结论 PLGA/Ⅰ型胶原复合支架具有良好的生物相容性,可作为构建组织工程阴道的支架材料。     

新型丝素蛋白多孔支架复合兔髓核细胞体外构建组织工程化髓核的实验研究

[目的]观察以新型丝素蛋白多孔支架复合兔髓核细胞体外构建组织工程化髓核的可行性。[方法]分离培养兔髓核细胞,与丝素蛋白多孔支架在体外复合培养,建立组织工程化髓核模型,通过扫描电镜、HE染色、甲苯胺蓝染色、Ⅱ型胶原免疫组化以及酶联免疫吸附测定观察细胞在支架上1周和3周的生长及增殖情况。[结果]培养1周后,扫描电镜显示细胞呈球状均匀地贴附在支架内部。细胞-支架复合体HE染色可见支架内部有大量髓核细胞,甲苯胺兰染色阳性,Ⅱ型胶原免疫组化染色阳性。培养3周后,扫描电镜显示细胞成层黏附于支架表面,细胞重叠生长,分泌大量细胞外基质,HE染色可见支架内部有大量髓核细胞填满支架孔隙并分泌大量细胞外基质,甲苯胺兰染色阳性,Ⅱ型胶原免疫组化染色阳性。酶联免疫吸附测定:3周组蛋白多糖含量(52.4±4.5)ng/ml明显高于1周组(29.3±3.6)ng/ml,P<0.05,3周组的II型胶原含量(24.3±1.8)ng/ml明显高于1周组(15.16±1.5)ng/ml,P<0.05。[结论]新型丝素蛋白多孔支架复合兔髓核细胞体外培养生长良好,分泌大量类似髓核样细胞外基质,可以用于体外构建组织工程化髓核。     

Ⅰ型胶原半月板支架负载纤维软骨细胞体外培养

[目的]观察Ⅰ型胶原半月板支架对纤维软骨细胞的吸附作用及对细胞生物学性状的影响，评价其作为半月板组织工程支架的可行性及价值。[方法]构建Ⅰ型胶原半月板支架，将体外培养的兔半月板纤维软骨细胞吸附于该支架上三维立体培养，通过相差倒置显微镜、组织学、扫描电镜及免疫组织化学检测支架对半月板纤维软骨细胞的表型、增殖及功能的影响。[结果]Ⅰ型胶原能制成理想大小、形状的三维立体多孔半月板支架，纤维软骨细胞在支架孔壁贴附良好，维持表型稳定，分泌胞外基质。[结论]Ⅰ型胶原半月板支架细胞相容性良好，但力学性能相对较差，通过与其它生物材料复合以提高其机械力学强度，可望制得理想的半月板组织工程支架。     

质粒修饰BMSC联合纳米支架促进软骨缺损修复的相关研究

目的探究慢病毒介导聚蛋白多糖(Aggrecan)过表达质粒转染骨髓间充质干细胞联合Gelatin/PLGA纳米纤维多孔支架向软骨细胞转化及软骨缺损修复的作用效果。方法构建慢病毒聚蛋白多糖过表达载体,培养骨髓间充质干细胞,构建兔模型软骨缺损模型,实验组造模后植入Gelatin/PLGA三维支架+转染聚蛋白多糖过表达载体骨髓间充质干细胞复合物;阴性对照组造模后植入Gelatin/PLGA三维支架+未转染骨髓间充质干细胞复合物;模型组造模后加入生理盐水处理。体外实验利用HE染色和免疫组织化学染色检测骨髓间充质干细胞联合Gelatin/PLGA纳米纤维多孔支架的联合培养体系向软骨细胞转化中聚蛋白多糖和Ⅱ型胶原蛋白的表达。构建兔膝关节软骨缺损模型,HE染色和免疫组织化学分析复合支架材料对软骨缺损的修复效果。结果 a)实验组(Gelatin/PLGA纳米纤维多孔支架+转染Aggrecan过表达载体骨髓间充质干细胞复合物)中支架表面黏附的细胞与对照组(Gelatin/PLGA纳米纤维多孔支架+未转染骨髓间充质干细胞)相比,细胞数明显增多;b)动物模型大体观察结果显示,实验组的修复效果要明显优于阴性对照组;c)动物模型HE染色结果显示,阴性对照组多为纤维性修复,而实验组多为细胞性修复;d)免疫组织化学染色结果显示,实验组修复软骨组织中Aggrecan和Ⅱ型胶原含量要明显优于阴性对照组。结论 Gelatin/PLGA三维支架加转染Aggrecan过表达载体骨髓间充质干细胞复合物可以促进BMSC向软骨细胞的分化,并且分泌更多的含Aggrecan和Ⅱ型胶原成分的细胞外基质,从而发挥其促进软骨缺损修复的作用。     

胶原涂层聚羟基丁酸羟基戊酸酯体外构建组织工程半月板

目的观察Ⅰ型胶原涂层的聚羟基丁酸羟基戊酸酯（PHBV）对半月板纤维软骨细胞的吸附作用及对细胞生物学性状的影响，评价其作为半月板组织工程支架的可行性及价值。方法构建Ⅰ型胶原涂层的PHBV半月板假体，将体外培养的兔半月板纤维软骨细胞吸附于该支架上三维立体培养。通过相差倒置显微镜、组织学、扫描电镜及免疫组织化学检测支架对半月板纤维软骨细胞的表型、增殖及功能的影响。结果PHBV能制成具有一定力学强度的半月板假体。通过Ⅰ型胶原涂层后增强了其细胞吸附能力，半月板纤维软骨细胞在支架孔壁贴附良好。维持表型稳定，分泌胞外基质。结论Ⅰ型胶原涂层的PHBV支架细胞相容性良好，能按半月板的大小、形状制成有一定力学强度的半月板假体，是比较理想的半月板组织工程支架材料。     

应用胶原凝胶构建组织工程化皮肤的研究

目的探讨以胶原凝胶为支架材料构建组织工程化皮肤的可行性。方法体外分离、培养人皮肤表皮细胞和成纤维细胞;利用自制的胶原蛋白制成胶原凝胶作为组织工程支架材料;在成功构建人工真皮的基础上种植表皮细胞,构建复合人工皮肤;采用HE染色与免疫组织化学的方法对复合人工皮肤进行组织学检测。结果HE染色可见,构建的复合人工皮肤具有表皮和真皮双层结构;免疫组织化学染色显示,Ⅳ型胶原、纤维连接蛋白和层粘连蛋白阳性,在形态结构上与正常皮肤相似。结论培养的人表皮细胞和成纤维细胞种植于胶原凝胶支架上,气-液界面培养可构建出具有类似正常皮肤结构的组织工程化皮肤。     

凝胶包埋脂肪基质细胞接受振荡载荷模式构筑工程化软骨的研究

目的 观察构建工程化软骨生物学行为,评估扩增软骨种子细胞的方法.方法 软骨诱导化脂肪基质细胞(ADSCs),接种至nβ-TCP/Cs/PCL支架构建工程化软骨:A组(凝胶+振荡培养)、B组(凝胶+静态培养)、C组(振荡培养)、D组(静态培养);每组48块构建物,各阶段每组随机取6块,第1、4、8、12、16、20、24、28天,电镜、共聚焦观察,检测存活率、细胞增殖、Ⅱ型胶原(Col-Ⅱ)、DNA及氨基葡聚糖(GAG)含量.结果 A组细胞生长旺盛、细胞外基质丰富,存活率高于其他组(86.39±5.05,P<0.05),增殖活力、Col-Ⅱ、DNA及GAG含量均高于其他组(0.57±0.12,71.30±2.51,73.21±1.38,81.25±1.29,P<0.05).结论 凝胶包埋及振荡方式能扩增种子细胞及优化软骨构建质量.     

以骨髓基质干细胞构建带内支撑的组织工程化软骨

目的 探讨构建特定形态带内支撑组织工程化软骨的医用假体的可能性.方法 以直径3 mm、长5 mm的圆柱状多孔高密度聚乙烯(Medpor)外裹厚1 mm的聚羟基乙酸为支架,将体外培养的骨髓基质干细胞(bone marrow stromal cells,BMSCs).按10×107/ml的细胞浓度均匀接种于支架,常规培养液培养5 d后,用含诱导因子的培养液立体诱导4周,同时以相同浓度的软骨细胞和BMSCs分别接种,常规体外培养4周作为阳性对照组和阴性对照组,分别种植于裸鼠皮下,4、8周后取材,行大体观察、组织学、组织化学、免疫组化及糖氨聚糖(GAG)定量等检测.结果 各组细胞均与材料粘附良好.实验组和阳性对照组均形成了大体形态良好的Medper-软骨复合体,内部的Medper与外层软骨结合紧密.组织学可见成熟软骨陷窝并渗入Medper孔隙内部、异染基质及Ⅱ型胶原表达,实验组GAG含量4、8周时分别为(5.13 ±0.32)mg/g、(5.37±0.12)mg/g.结论 以BMSCs作为种子细胞可于体内构建特定形态、组织学良好的Medpor-软骨复合体.     

增强型生物活性玻璃-胶原复合支架材料的成骨效能研究

目的 探讨增强型生物活性玻璃-胶原复合支架材料的体内外成骨效能.方法取第3代BMSCs种植于支架材料(支架组),以等量细胞常规培养作为非支架组,培养1、3、5、7、9、11 d采用阿尔玛蓝法动态检测细胞的增殖率.取第3代BMSCs种植于支架材料(体外实验组),以等量细胞常规培养作为体外对照组,培养4、7 d采用实时定量逆转录聚合酶链式反应(qRT-PCR)检测细胞骨形态发生蛋白-2(BMP-2)、碱性磷酸酶(ALP)、Ⅰ型胶原的mRNA表达.裸鼠皮下植入复合成骨样细胞的支架材料(体内实验组),取正常骨组织作为体内对照组,6周后以X线片、qRT-PCR、绀织学染色评估成骨情况.结果培养7～11 d支架组细胞增殖率显著高于非支架组,差异均有统计学意义(P<0.05).体外实验组培养7 d BMP-2、ALP、Ⅰ型胶原的mRNA表达显著高于体外对照组,差异均有统计学意义(P<0.05).体内实验组X线片示植入区域有密度增高影,支架材料形成白色硬性组织;BMP-2、Ⅰ型胶原、骨钙素、骨桥蛋白的mRNA表达较体内埘照组均增高,差异有统计学意义(P<0.05);组织学染色示支架材料大部分降解,新生骨形成明显.结论增强型生物活性玻璃-胶原复合支架材料具有良好的生物相容性,体内外均具有成骨效应.

Abstract：

Objective To study the in vivo and vitro biocompatibility and osteogenetic capacity of enhanced bioactive glass/collagen composite scaffold. Methods Bone marrow stromal cells(BMSCs)were collected and induced to osteoblast-like cells.The growth rate of BMSCs was detected and compared progressively through Alamar Blue.The RNAs of the cells were collected and detected for bone morphogenetic protein-2(BMP-2),alkaline phosphatase(ALP),collagen Ⅰ(Col-Ⅰ)through qRT-PCR on the fourth and seventh days.Scaffolds with induced osteoblasts were embedded into 3 nude mice subcutaneously in vivo and detected after 6 weeks.X-ray,qRT-PCR and tissue staining were used to detect the mRNA expressions of BMP-2,Col Ⅰ,osteocalcin(OCN)and ostcopontin(OPN)and bone formation. Results SEM(scanning electronic microscopy)showed BMSCs attached to the scaffold tightly and viably and proliferated actively on the scaffold.The growth rate in the experimental group was significantly higher after 7 days(P<0.05)than in the control group.qRT-PCR showed that the mRNA expressions of BMP-2,ALP and Col-Ⅰ in the experimental group were significantly higher than in the control group on the seventh day(P<0.05).X-ray showed that the dense images of embedded scaffolds were locally similar to those of normal bone after 6 weeks.qRT-PCR showed that the mRNA expressions of BMP-2,Col Ⅰ,OCN and OPN in the experimental group were significantly higher than those of normal bone(P<0.05).HE and Massort staining of the paraffin sections showed the scaffolds degraded generally and osteoblasts and chondrocytes proliferated abundantly and distributed irregularly.Bone formation could be observed obviously. Conclusion Enhanced bioactive glass/collagen composite scaffolds have good biocompatibility and osteogenetic capacity in vitro and vivo.     

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.     

同种异体脱钙骨复合骨髓间充质干细胞在兔膝关节腔内培养组织工程软骨的研究

目的 比较同种异体脱钙骨和细胞因子诱导骨髓间充质干细胞(BMSC)制成细胞-支架复合物在兔膝关节腔内环境较体外培养出组织工程软骨的优点.方法 BMSC向软骨细胞诱导后与同种异体脱钙骨支架复合分别在体外培养(A组)和成年雄性新西兰白兔(15只)左侧膝关节腔内(B组)培养,右侧膝关节腔内(C组)培养单纯脱钙骨支架做空白对照.每4、8、12周各组标本分别取材,制石蜡切片行苏木素-伊红(HE)染色、甲苯胺蓝染色、Ⅱ型胶原免疫组织化学等组织学观察,并通过形态学分析软件计算免疫组织化学平均光度(A)值.结果 标本石蜡切片HE染色:4周时A组标本见软骨细胞散在分布于支架表面,内部基本未观察到细胞.B组标本支架内软骨细胞数量明显较多,软骨陷窝形成,陷窝周围基质深染,可见由单个细胞分裂形成的同源细胞群.8周时B组标本以成熟软骨细胞为主,细胞数量多,出现柱状排列的同源细胞群,细胞周围分泌着色均一的玻璃样基质,且渗入支架结构内部,脱钙骨支架有部分被吸收.12周时各组支架结构明显被吸收,A组支架内填满软骨细胞,部分已纤维化,但结构排列紊乱.B组支架呈透明软骨样,软骨细胞充分渗透进入支架内,呈一定应力方向排列.Ⅱ型胶原免疫组织化学A值统计学分析比较发现:第4,8,12周B组Ⅱ型胶原免疫组织化学的A值均高于A组,差异有统计学意义(P＜0.01).两组间A值随时间的变化趋势差异有统计学意义(P＜0.01).结论 同种异体脱钙骨支架复合经细胞因子诱导的BMSC,在膝关节腔内进行培养,利用关节腔内低氧、多种生长因子的微环境以及关节活动时的应力刺激等优势,较体外培养可以培养出组织学特点更好的工程软骨.

Abstract：

Objective To compare the superiority of cultivating tissue engineered cartilage by homologous decalcified bone matrix combined with bone-marrow mesenchymal stem cells (BMSCs) in rabbits' knee cavity with culture in vitro. Methods Archiogeneration BMSCs were isolated and purified by adhering to the culture glassware wall from neonatal New Zealand white rabbits. The third generation BMSCs were induced to chondrocytes by transforming growth factor TGF-β1, insulin-like growth factor IGF-1 and vitamin C. Seven days later, the cells were bond to homologous decalcified bone matrix and cultured in vitro (group A) , cultured in rabbits' left knee cavity (group B) , or bond to homologous decalcified bone matrix and cultured in rabbits' right knee cavity ( group C ). Every 4 weeks after cellular transplant, all rabbits in groups B and C were sacrificed and paraffin-embedded sections were made from the specimens.All the section were subjected to H-E stain, toluidine blue stain and type Ⅱ collagen immunohistochemical staining with chromogen diaminobenzidine ( DAB) . Immunohistochemical absorbance ( A) values were calculated by morphology analysis software. Measurement data were expressed as mean ± standard, and satistical analysis was performed by t test, one-way ANOVA using SPSS 15. 0 software. Results After cultivation for 4 weeks, H-E stain showed diffuse distribution of chondrocytes on scaffold' s surface in group A.In group B, there were a great quantity of chondrocytes in the scaffold, and cartilage lacuna, matrix anachromasis and isogenous group were group. At the 8th week, in group B maturated chondrocytes and isogenous groups arranged as column, surrounded by a pond of cellular matrix infiltrating into the scaffolds. The decalcified bone matrix was absorbed partly. At the 12th week, all the scaffolds were absorbed obviously.Chondrocytes filled into the scaffolds in group A, but arranged irregularly. In group B chondrocytes arranged in the stress orientation. At 4th, 8th, and 12th week, A values of type Ⅱ collagen in group B was significantly higher than in group A with the different being significant. Conclusion Compound of Homologous decalcified bone matrix-induced BMSCs cultured in rabbits' knee cavity could yield better histological feature tissue engineered cartilage.     

The effects of bone marrow-derived mesenchymal stem cells and fascia wrap application to anterior cruciate ligament tissue engineering

After an anterior cruciate ligament (ACL) injury, surgical reconstructions are necessary in most cases, either with autografts, allografts, or artificial ligaments. Potential tissue-engineered ligaments would circumvent the disadvantages apparent in these methods. While seeding of mesenchymal stem cells (MSCs) and fascia wrap could potentially improve tissue regeneration and mechanical properties, their exact roles were evaluated in the current study. Knitted biodegradable scaffolds of poly-L-lactic acid (PLLA) and poly-glycolic-lactic acid (PGLA) yarns were used to reconstruct ACL in 48 rabbits. These were divided into four equal groups: only knitted scaffolds were used in group I; knitted scaffolds and mesenchymal stem cells were used in group II; knitted scaffolds, MSCs, and fascia lata were used in group III; knitted scaffolds and fascia lata were used in group IV. Carboxyfluorescein diacetate (CFDA)-labeled MSCs were used to trace the fate of seeded cells in groups II and III. Histology, Western blot analysis, and mechanical properties of reconstructed ACL were analyzed after 20 weeks. Fibroblast ingrowths were seen in all four groups while CFDA-labeled MSCs could be found after 8 weeks of implantation in groups II and III. Both the amount of collagen type I and collagen type III in groups III and IV were significantly higher than in group II, which was much higher than in group I. Both maximal tensile loads and stiffness of the reconstructed ACLs in groups I, II, III, and IV were significantly lower than normal controls after 20 weeks of implantation. It is concluded that MSCs could promote synthesis of collagen type I and collagen type III in tissue-engineered ligaments, while fascia wraps have stronger effects. Both MSC seeding and fascia wrap could not enhance ultimate tensile load and stiffness.     

力学刺激促进软骨细胞与骨髓基质干细胞共培养体外软骨分化

目的：研究不同的应力刺激对软骨细胞与骨髓基质干细胞（BMSCs）共培养体外构建组织工程化软骨的影响。方法：分离、培养、扩传兔MSCs及软骨细胞,二者按7：3比例混和,以5．0×107／ml的细胞密度接种于聚羟基乙酸（PGA）支架上,一周后根据不同的施加力分为4组：离心组、摇床组、搅拌组,静止培养作为对照组。6周后取材行相关检测。结果：三受力组形成的细胞材料复合物基本保持原来的体积与外形。HE染色结果显示大量成熟软骨陷窝形成,细胞外基质沉积均匀;Safranin-O及甲苯胺兰染色显示有大量的GAG形成,免疫组化检测II型胶原表达强阳性。三受力组标本组织湿重、体积、GAG含量等指标均优于对照组。结论：力学刺激有利于促进少量软骨细胞与BMSCs共培养体外软骨分化;并在三维支架材料上构建组织工程化软骨。     

异体颗粒状脱细胞真皮基质与自体刃厚皮复合移植修复大鼠皮肤缺损创面效果观察

目的 观察异体颗粒状脱细胞真皮基质(PADM)与自体刃厚皮复合移植修复大鼠皮肤缺损创面的效果.方法 采用随机数字表法将12只SD大鼠分为实验组和对照组,每组6只.于2组大鼠背部制作全层皮肤缺损创面,实验组创面复合移植SD大鼠异体PADM(扩张比10:5)及厚度0.20 mm的自体刃厚皮,对照组创面仅移植厚度0.20 mm自体刃厚皮.术后2周起打开敷料观察大鼠创面愈合情况.术后2、3、4、6、8、12、20周计算2组创面移植皮片成活率、收缩率(或扩张率).术后20周取2组创周正常皮肤及创面皮肤标本,采用HE染色法观察胶原纤维束结构,测量胶原纤维束直径和间隙率;用天狼星红染色法观察Ⅰ、Ⅲ型胶原分布情况,测量Ⅰ、Ⅲ型胶原含量及其比值.对实验数据行独立样本t检验、Levene检验、t'检验.结果 (1)术后2周,实验组大鼠创面移植皮片成活率[(76.1±13.1)%]低于对照组[(94.5±1.3)%,t'=3.440,P=0.018].术后3周,实验组创面移植皮片收缩率[(34±8)%]明显大于对照组[(16±12)%,t=-3.211,P=0.009];术后8周,2组移植皮片扩张率接近一致.(2)HE染色和天狼星红染色显示,与大鼠创周正常皮肤比较,对照组移植皮片胶原纤维束呈均质化改变,胶原纤维纤细,排列紊乱;实验组移植皮片胶原纤维束结构、排列更接近创周正常皮肤,可见未完全降解的PADM.与对照组创面皮肤胶原纤维束直径[(7.3±1.4)μm]、间隙率[(17±4)%]、Ⅰ型胶原含量[(68.1±8.4)%]、Ⅲ型胶原含量[(32.0±8.4)%]以及Ⅰ、Ⅲ型胶原比例(2.3±1.0)比较,实验组胶原纤维束更粗[(9.6±0.8)μm,t=-3.562,P=0.005],间隙率更大[(24±5)%,t=-2.760,P=0.020],Ⅰ型胶原含量更高[(80.2±5.4)%,t=-2.981,P=0.014],Ⅲ型胶原含量更低[(19.8±5.4)%,t=2.981,P=0.014],Ⅰ、Ⅲ型胶原比例更高(4.3±1.2,t=-3.204,P=0.009).实验组创面皮肤上述胶原相关指标更接近于创周正常皮肤水平.结论 异体PADM在体内作为真皮再生模板,有助于改善自体刃厚皮所修复的大鼠皮肤缺损创面中真皮胶原纤维束的结构,提高再生真皮组织的成熟度.

Abstract：

Objective To evaluate the effects of mixed grafting of allogeneic PADM and autologous STS on wound healing of full-thickness defect in rats. Methods Full-thickness defects with size of 6 cm×4 cm were produced on the back of 12 SD rats, and they were divided into E group(n =6) and C group ( n = 6) according to the random number table. The wounds in E group were grafted with a mix of allogeneic PADM (expansion rate 10: 5) and autologous STS with thickness of 0.2 mm, while those in C group were grafted with autologous STS in the same thickness. The wound healing rate, survival rate, contraction rate,and expansion rate of transplanted skin were observed at post operation week (POW) 2, 3, 4, 6, 8, 12,20. Tissue samples form wounds and surrounding normal skin were harvested at POW 20 for histopathological observation as follows. The structure of collagen fiber bundle was observed by HE staining, the diameter and gap rate of collagen fiber bundle were also measured. The distribution of type Ⅰ and Ⅲ collagen was observed by sirsus red staining, and the contents of type Ⅰ , Ⅲ collagen and their ratio were also examined.Data were processed with independent samples t test, Levene test, and t' test. Results Survial rate of transplanted skin in E group at POW 2 [(76. 1 ± 13. 1)%] was obviously lower than that in C group [(94.5 ± 1.3)%, t' =3.440, P =0.018]. Contraction rate of transplanted skin in E, C groups at POW 3 showed significant difference [(34±8)%vs. (16 ±12)%, t = -3.211, P =0.009]. Compared with those in peri-wound normal skin, collagen fiber bundles in C group showed signs of homogenization, and collagen fibers were thin with irregular arrangement. Collagen fiber structure and arrangement of composite skin in E group were similar to those surrounding normal skin with incomplete degradation of PADM. Diameter of collagen fiber bundle [( 9.6 ± 0.8) μm] , gap rate between collagen bundle [( 24±5) %] , content of type Ⅰ collagen [( 80.2 ± 5.4) %] and the ratio of typeⅠto type Ⅲ collagen(4.3 ± 1.2) in E group were all increased as compared with those inC group [(7.3±1.4) μm (t = -3.562, P =0.005), (17±4)%( t =-2.760, P =0.020), (68.1 ±8.4)%(t = -2.981, P =0.014), 2.3±1.0(t = -3.204, P =0. 009)], while content of type Ⅲ collagen [( 19.8 ± 5.4) %] in E group was lower than that in C group [(32.0 ±8.4)% , t = 2. 981, P = 0. 014]. Above-mentioned indexes of collagen in wound of E group were similar to those of normal skin surrounding the wound. Conclusions Allogeneic PADM used as dermal regeneration template is beneficial in improving collagen fiber bundle structure in dermis layer of rats with fullthickness skin wounds when repaired with autologous STS, and it accelerates maturation of regenerative dermal tissue.     

PRP及RGD联合修饰表面改性后仿生基质对ADSCs生物学行为的调控

目的 评估富血小板血浆(platelet rich plasma,PRP)及精氨酸-甘氨酸-天冬氨酸(Arg-Gly-Asp,RGD)联合修饰表面改性后支架的细胞生物学特征,验证优化界面整合的方法.方法 兔脂肪基质干细胞成骨诱导化,nβ-TCP/Cs/PCL仿生基质Nd:YAG激光处理,表面改性及细胞接种:A组(PRP凝胶加RGD修饰表面改性基质加ADSCs)、B组(RGD修饰表面改性基质加ADSCs)、C组(表面改性基质加ADSCs)、D组(未表面改性基质加ADSCs);第1、4、8、12、16、20、24、28天,显微镜和电镜、共聚焦技术观察和检测细胞的存活率、增殖活力、Westen blot测定碱性磷酸酶及Ⅰ型胶原蛋白表达活性,分析Runx2与OPG表达.结果 A组细胞生长旺盛、细胞外基质丰富,存活率高于其它组(88.16±1.29,P＜0.05),增殖活力、碱性磷酸酶及Ⅰ型胶原水平均高于其它组(0.92±0.13,87.27±3.08,93.27±3.91,P＜0.05),Runx2和OPG表达显著.结论 PRP及RGD修饰联合支架表面改性能促进细胞增殖,为理想的骨整合方法.     

松质骨基质复合生物蛋白胶构建组织工程软骨的研究

目的尝试采用松质骨基质与生物蛋白胶复合材料构建组织工程软骨。方法体外培养大鼠软骨细胞,接种于松质骨基质／生物蛋白胶材料上行体外培养。采用HE、甲苯胺蓝染色免疫学检测、扫描电镜观察等方法观察所构建的组织工程软骨的特性。结果松质骨基质／生物蛋白胶组的组织学结构更接近于软骨样组织．其Ⅱ型胶原、蛋白多糖基因表达量及蛋白多糖含量明显高于松质骨基质组。结论松质骨基质／生物蛋白胶复合材料可用于构建组织工程软骨,是一种较理想的支架材料。