软骨细胞与骨髓基质细胞共培养体外构建软骨组织的实验研究

目的 探讨利用软骨细胞提供的软骨微环境诱导骨髓基质细胞(BMSC)在体外构建软骨组织的可行性.方法 将分离出的猪骨髓基质细胞和软骨细胞进行体外培养,收集软骨细胞培养上清液,作为骨髓基质细胞诱导液从第2代开始进行诱导分化.7 d后取出标本,免疫组织化学检测软骨特异性Ⅱ型胶原表达,RT-PCR检测Ⅱ型胶原和aggrecan的mRNA表达.体外分离培养的骨髓基质细胞与软骨细胞,扩增后两者以8∶2比例混匀,以5.0×107/ml的终浓度接种于聚羟基乙酸/聚乳酸(PGA/PLA)支架,以相同浓度的单纯软骨细胞和单纯BMSC以及20%上述浓度(1.0×107/ml)的单纯软骨细胞作为对照组.标本于8周后取材,行大体观察、湿重、蛋白多糖(GAGs)含量测定、组织学及免疫组化等相关检测.结果 经诱导后的骨髓基质细胞的Ⅱ型胶原免疫组化检测阳性,RT-PCR检测Ⅱ型胶原和aggrecan mRNA呈阳性表达.混合细胞组及阳性对照组体外培养8周后形成了单一成熟的软骨组织,并保持了支架材料的大小和形状,两组新生软骨在外观及组织学特征上也基本相同,免疫组化结果 表明两组均大量表达软骨特异性细胞外基质Ⅱ型胶原,共培养组的平均湿重和蛋白多糖(GAGs)含量均达到阳性对照组的70%以上.而单纯骨髓基质细胞组仅在局部形成了极少量幼稚的软骨样组织,且材料支架明显皱缩变形.低软骨细胞浓度组虽新生软骨湿重量能达阳性对照组的30%,但材料支架明显皱缩变形,仅在局部形成了不连续的软骨组织,新生软骨量明显少于共培养各组及阳性对照组.结论 软骨细胞能在一定程度上提供软骨形成的微环境,有效地诱导BMSC向软骨细胞分化,并在体外形成组织工程化的软骨组织.

Abstract：

Objective To investigate the feasibility of chondrogenesis in vitro with bone marrow stromal cells (BMSCs) induced by the co-cultured chondrocytes. Methods The BMSCs and chondrocytes were separated from pig and cultured. The supernatant of chondrocytes was used as the inducing solution for BMSCs from the 2nd generation. 7 days later, samples were taken and underwent immunohistochemistry and RT-PCR for detection of the expression of specific type Ⅱ cartilage collagen,type Ⅱ collagen and aggrecan mRNA. The cultured BMSCs and chondrocytes were mixed at a ratio of 8:2(BMSC: cartilage cell) and were inoculated into a polyglycolic acid/polylactic acid (PGA/PLA) scaffold at the final concentration of 5.0 × 107/ml. The cartilage cells and BMSCs were also inoculated seperately at the same concentration as the positive and negative control. Pure cartilage cells at 20% of the abovementioned concentration (1.0 × 107/ml) were used as the low concentration cartilage cell control group. Samples were collected 8 weeks later. General observations, wet weight, glycosaminoglycans (GAGs) determination and histological and immunohistochemistry examinations were performed. Results The expression of type Ⅱ collagen, type Ⅱ collagen and aggrecan mRNA were positive in induced BMSCs.In the co-cultured group and the positive control group, pure mature cartilage was formed after 8 weeks of culture in vitro, and the size and shape of the scaffold were maintained. The newly formed cartilage in the two groups were almost the same in appearance and histological properties. The immunohistochemistry results indicated that the cartilage cells of the two groups all expressed ample cartilage-specific type Ⅱ collagen. The average wet weight and GAG content in the co-cultured group reached more than 70% of those in positive control group. Only an extremely small amount of immature cartilage tissues was formed in local regions in pure BMSC group, and the scaffold was obviously shrunk and deformed. Although the wet weight of newly generated cartilage tissue in the low concentration cartilage cell group reached 30% of that in positive control group, the scaffold was obviously shrunken and deformed. Only regional and discontinuous cartilage tissues were formed, and the amount of newly formed cartilage was obviously less than that in the co-culture group and the positive control group. Conclusions Chondrocytes can provide a micro-environment for the formation of cartilage, and also effectively induce BMSC to differentiate into chondrocytes and form tissue-engineered cartilage in vitro.     

软骨细胞与骨髓基质细胞共培养体外构建软骨组织的实验研究

Objective To investigate the feasibility of chondrogenesis in vitro with bone marrow stromal cells (BMSCs) induced by the co-cultured chondrocytes. Methods The BMSCs and chondrocytes were separated from pig and cultured. The supernatant of chondrocytes was used as the inducing solution for BMSCs from the 2nd generation. 7 days later, samples were taken and underwent immunohistochemistry and RT-PCR for detection of the expression of specific type Ⅱ cartilage collagen,type Ⅱ collagen and aggrecan mRNA. The cultured BMSCs and chondrocytes were mixed at a ratio of 8:2(BMSC: cartilage cell) and were inoculated into a polyglycolic acid/polylactic acid (PGA/PLA) scaffold at the final concentration of 5.0 × 107/ml. The cartilage cells and BMSCs were also inoculated seperately at the same concentration as the positive and negative control. Pure cartilage cells at 20% of the abovementioned concentration (1.0 × 107/ml) were used as the low concentration cartilage cell control group. Samples were collected 8 weeks later. General observations, wet weight, glycosaminoglycans (GAGs) determination and histological and immunohistochemistry examinations were performed. Results The expression of type Ⅱ collagen, type Ⅱ collagen and aggrecan mRNA were positive in induced BMSCs.In the co-cultured group and the positive control group, pure mature cartilage was formed after 8 weeks of culture in vitro, and the size and shape of the scaffold were maintained. The newly formed cartilage in the two groups were almost the same in appearance and histological properties. The immunohistochemistry results indicated that the cartilage cells of the two groups all expressed ample cartilage-specific type Ⅱ collagen. The average wet weight and GAG content in the co-cultured group reached more than 70% of those in positive control group. Only an extremely small amount of immature cartilage tissues was formed in local regions in pure BMSC group, and the scaffold was obviously shrunk and deformed. Although the wet weight of newly generated cartilage tissue in the low concentration cartilage cell group reached 30% of that in positive control group, the scaffold was obviously shrunken and deformed. Only regional and discontinuous cartilage tissues were formed, and the amount of newly formed cartilage was obviously less than that in the co-culture group and the positive control group. Conclusions Chondrocytes can provide a micro-environment for the formation of cartilage, and also effectively induce BMSC to differentiate into chondrocytes and form tissue-engineered cartilage in vitro.     

软骨细胞与骨髓基质细胞共培养体外构建软骨组织的实验研究

Objective To investigate the feasibility of chondrogenesis in vitro with bone marrow stromal cells (BMSCs) induced by the co-cultured chondrocytes. Methods The BMSCs and chondrocytes were separated from pig and cultured. The supernatant of chondrocytes was used as the inducing solution for BMSCs from the 2nd generation. 7 days later, samples were taken and underwent immunohistochemistry and RT-PCR for detection of the expression of specific type Ⅱ cartilage collagen,type Ⅱ collagen and aggrecan mRNA. The cultured BMSCs and chondrocytes were mixed at a ratio of 8:2(BMSC: cartilage cell) and were inoculated into a polyglycolic acid/polylactic acid (PGA/PLA) scaffold at the final concentration of 5.0 × 107/ml. The cartilage cells and BMSCs were also inoculated seperately at the same concentration as the positive and negative control. Pure cartilage cells at 20% of the abovementioned concentration (1.0 × 107/ml) were used as the low concentration cartilage cell control group. Samples were collected 8 weeks later. General observations, wet weight, glycosaminoglycans (GAGs) determination and histological and immunohistochemistry examinations were performed. Results The expression of type Ⅱ collagen, type Ⅱ collagen and aggrecan mRNA were positive in induced BMSCs.In the co-cultured group and the positive control group, pure mature cartilage was formed after 8 weeks of culture in vitro, and the size and shape of the scaffold were maintained. The newly formed cartilage in the two groups were almost the same in appearance and histological properties. The immunohistochemistry results indicated that the cartilage cells of the two groups all expressed ample cartilage-specific type Ⅱ collagen. The average wet weight and GAG content in the co-cultured group reached more than 70% of those in positive control group. Only an extremely small amount of immature cartilage tissues was formed in local regions in pure BMSC group, and the scaffold was obviously shrunk and deformed. Although the wet weight of newly generated cartilage tissue in the low concentration cartilage cell group reached 30% of that in positive control group, the scaffold was obviously shrunken and deformed. Only regional and discontinuous cartilage tissues were formed, and the amount of newly formed cartilage was obviously less than that in the co-culture group and the positive control group. Conclusions Chondrocytes can provide a micro-environment for the formation of cartilage, and also effectively induce BMSC to differentiate into chondrocytes and form tissue-engineered cartilage in vitro.     

地塞米松对骨髓基质细胞生物学特性的影响

目的 探讨地塞米松对体外培养的骨髓基质细胞增殖和分化等生物学特性的影响。方法 取4－6周龄新西兰兔双侧股骨骨髓3ml,体外分离,培养至第3代骨髓基质细胞,分别用地塞松浓度为0、10^10、10^-9、10^-8、10^-7和10^-6mol/L的培养基,作用2、4、及6天后,测定骨髓基质细胞的分裂增殖能力和碱性磷酸酶活性。结果 地塞米松对骨髓基质细胞的增殖起抑制作用,并随地塞米松浓度的升高而增强,其浓度大于10^-8mol/L后抑制作用越显著。地塞米松在抑制增殖的同时,可显著增强骨髓基质细胞的碱性磷酸酶活性,浓度越高作用也越显著,但超过10^-8mol/L后各浓度的作用效果无显著差别;这种作用随时间的延长而增强,至6天时与对照组相比可增强2－4倍。结论 地塞米松抑制骨髓基质细胞的增殖,但可促进其分化成骨细胞, 浓度为10^-8mol/L较合适。     

骨髓基质细胞源性软骨细胞修复兔全层关节软骨缺损

目的观察体外诱导骨髓基质细胞(MSCs)源性软骨细胞在兔股骨滑车关节面全层软骨缺损修复中的作用. 方法高密度传代培养第3代诱导MSCs分化为软骨细胞,以酸溶性Ⅰ型胶原为载体,两者混合后形成凝胶样植入物(细胞浓度为5×106/ml).于36只新西兰大耳白兔一侧股骨滑车关节面造成3 mm×5 mm全层关节软骨缺损,凝胶样植入为实验侧;另一侧分别为单纯胶原植入组(18个膝关节)和空白对照组(18个膝关节).术后4、8、12、24、32和48周取材观察缺损修复情况及新生组织的类型.参照Pineda标准对新生组织评分. 结果实验侧术后4周,植入细胞类似软骨细胞,周围有异染基质,形成透明软骨样组织;8周,深层有软骨下骨形成,软骨细胞层较正常关节软骨厚;12周,新生软骨厚度减小,与正常软骨相近,细胞呈柱状排列,结构与正常关节软骨相似,软骨下骨形成,潮线恢复;24周,新生软骨厚度较正常薄,约占55%,表面平整,潮线附近仍有肥大的软骨细胞;32周,潮线附近无肥大软骨细胞;48周,组织结构与32周时基本相同,为类透明软骨.Pineda评分24、32和48周间无差异,与4周比较有统计学意义(P＜0.05).实验组2～48周期间关节功能良好.单纯胶原组与空白对照组缺损无修复,48周时软骨下骨外露,关节退变;关节功能逐渐减退,动度受限. 结论 MSCs源性软骨细胞移植体内可形成透明样软骨组织,24周后新生软骨特性稳定,48周时为透明样软骨,能维持良好的关节功能.     

软骨细胞诱导骨髓基质细胞构建软骨的体内外比较

目的 应用软骨细胞诱导骨髓基质细胞(Bone Marrow Stromal Cells,BMSCs)体外构建软骨,比较其体内植入前后软骨相关生物学特性的差异,探讨共培养构建软骨临床应用的可行性.方法 体外分别培养扩增猪关节软骨细胞和BMSCs,两者按2:8比例混合(软骨细胞:BMSC),以5.0×107/ml的细胞终浓度接种于聚乳酸包埋的聚羟基乙酸支架,体外培养8周后部分标本植入裸鼠皮下,再经体内8周后取材.通过大体观察、糖胺聚糖含量(GAG)测定、生物力学测试、组织学,以及免疫组化等方法对体内植入前后标本的软骨相关生物学特性进行比较.结果 体外培养8周时,所有标本均形成了软骨样组织,但质地较软,组织结构相对较为松散.体内植入8周后,共培养构建软骨能维持良好的软骨外观,而且GAG含量及弹性模量均明显高于体外标本(p＜0.01),组织学及免疫组化显示体内标本的组织结构致密,基质及Ⅱ型胶原显色程度均明显强于体外标本.结论 软骨细胞诱导BMSCs构建的软骨在体内皮下环境中能维持良好的软骨特性,而且植入体内后能继续向成熟软骨发育.     

不同类型人软骨细胞体外生物学特性比较

目的　通过研究人耳软骨和肋软骨两种不同类型软骨细胞体外分离、增殖、老化规律 ,为选择合适的组织工程种子细胞提供依据。方法　取小耳畸形残耳软骨和肋软骨 ,体外分别用0 .0 5 %和 0 .15 %Ⅱ型胶原酶消化 16h分离 ,台盼蓝染色计活细胞数 ,得原代细胞获得率。体外单层培养 6代 ,观察形态学改变 ,群体倍增时间 (PDT ) ,免疫细胞化学染色及逆转录 聚合酶链反应(RT PCR)检测Ⅱ型胶原和Aggrecan评定软骨细胞老化规律。 结果　人残耳软骨组织平均细胞获得率为 ( 1.5 4± 0 .14 )× 10 6/ g ,肋软骨平均获得率为 ( 0 .46± 0 .0 9)× 10 6/ g ,两类软骨细胞P1的PDT最短 ,前 3代增殖力较强 ,P3 以后PDT明显延长 ,P6代细胞不再增殖。免疫细胞化学及RT PCR均证实耳软骨细胞 3代内、肋软骨细胞 4代内软骨细胞表型稳定。结论　第 2代的耳软骨细胞与第 3代肋软骨细胞可作为人体内组织工程化软骨构建的种子细胞。     

pcDNA3-hBMP2转染兔骨髓基质细胞前后生长特性的研究

目的 观察pcDNA3-hBMP2转染兔骨髓基质细胞前后的生长特性变化,为骨组织工程的种子细胞选择打下基础.方法 抽取成年雄性新西兰大白兔髂骨骨髓,密度梯度离心获得骨髓基质细胞,培养传至第5代,按处理方法分为常规培养液组(A组),pcDNA3-hBMP2转染组(B组).观察原代MSC及第5代的细胞形态等生长特性并与转染组进行比较.结果 原代MSCs为短梭形,簇形生长,传代细胞呈长梭形,旋涡形生长.转染组细胞72 h后表达BMP2,瞬问表达为100%.转染细胞未经筛选培养4周细胞形态发生较明显地变化,细胞生长周期改变.结论 pcDNA3-hBMP2成功转染兔骨髓基质细胞并改变其生物学特性.     

骨髓基质细胞与两种不同载体材料生物相容性的实验研究

目的 :采用体外细胞培养法对 2种不同生物材料 (胶原海绵和PLGA )的生物相容性进行研究 ,探讨它们作为软骨组织工程载体材料的可行性。方法 :取 2个月龄新西兰兔 ,麻醉后在无菌条件下自双侧股骨粗隆处用 16号穿刺针抽取骨髓 4～ 6ml,用D -Hanks液洗涤离心 2遍 ( 10 0 0rpm× 10min) ,悬浮于含 10 %FBS的DMEM培养液中 ,行原代及传代培养 ,将传代细胞以 1 5× 10 4/孔定量接种于 2 4孔培养板 ,每孔加DMEM培养液 1ml。实验分为 3组 ,即PLGA组、胶原海绵组和对照组 ,其中PLGA组、胶原海绵组分别加入直径 5mm ,厚度 2mm大小的材料 ,对照组单纯接种细胞 ,于不同时间进行处理 ,用于相差显微镜及扫描电镜观察 ,绘制生长曲线 ,流式细胞仪检测。结果 :骨髓基质细胞可以在胶原海绵和PLGA周围生长 ,逐渐粘附 ,并在其表面连接成片 ,分泌细胞外基质 ;对照组与实验组、各实验组之间生长曲线相近 ,统计学分析无显著性差异 ;流式细胞仪 (FCM )检测发现 2种材料对细胞周期无影响 ,未发现异倍体细胞。结论 :胶原海绵和PLGA对兔MSC的形态学、细胞生长增殖、细胞周期、DNA含量及倍体水平均无影响 ,2种生物材料具有良好的生物相容性 ,可作为软骨组织工程的载体材料安全应用。     

胎盘间充质干细胞与骨髓间充质干细胞分离培养和生物学特性研究

目的探讨兔胎盘间充质干细胞(placenta-derived mesenchymal stem cells,PMSCs)和兔骨髓间充质干细胞(bone marrow-derived MSCs,BMSCs)体外分离培养、增殖,对其生物学性状进行比较观察。方法取足月待产新西兰大耳白兔1只,采用密度梯度离心法及贴壁培养技术从兔胎盘对PMSCs进行分离、纯化和传代培养。取2周龄新西兰大耳白兔1只,采用直接贴壁法从后肢骨髓中对BMSCs进行分离、纯化和传代培养。用倒置相差显微镜观察两种细胞形态。免疫组织化学染色对第3代细胞表面标志(CD44、CD105、CD34、CD40L)进行鉴定。将BMSCs与PMSCs第2代细胞分别与生物衍生骨进行复合培养5d,每条材料接种(1.0~1.5)×106个细胞,苏木素染色观察细胞与材料复合培养情况。扫描电镜观察两种细胞分别与材料复合培养3d和8d的情况。结果在倒置相差显微镜下观察,两种细胞均为贴壁生长,形态为均一成纤维细胞样。PMSCs增殖力强,细胞的增殖能力随传代次数的增加而有所下降,细胞体外培养10代后,生长速度减慢。两种细胞均表达CD44、CD105,不表达CD34、CD40L。复合培养5d,PMSCs和BMSCs在生物衍生骨表面生长,大量黏附,细胞积聚成团,相互连接成网状,孔隙内也可见细胞生长和增殖,并分泌基质。扫描电镜观察:复合培养3d,可见较多量的细胞在生物衍生骨上黏附,呈梭形或多角形;8d两种细胞均已大量增长,呈层状排列,细胞连接紧密,分泌大量基质,细胞周围有较多的网状胶原形成。结论PMSCs与BMSCs有相似的生物学特性,可作为组织工程的另一成体干细胞来源。     

骨髓基质细胞与生物活性玻璃陶瓷和聚乳酸生物相容性的实验研究

目的 探讨骨髓基质细胞与生物活性玻璃陶瓷（ＢＧＣ）和聚乳酸（ＰＬＡ）的生物相容性,为骨组织工程中生物材料的选择提供依据。方法 将骨髓基质细胞与ＢＧＣ、ＰＬＡ复合体培养,进行形态学观察、细胞增殖、蛋白质含量及酶学测定。结果 骨髓基质细胞能在ＢＧＣ、ＰＬＡ上贴附、繁殖,其生长及功能不受影响,并且ＢＧＣ具有一定的促细胞增殖作用。结论 ＢＧＣ、ＰＬＡ具有良好的细胞相容性,有可能作为骨髓基质细胞的载体应用于     

转化人胚肌腱细胞的体外培养及生物学特性研究

目的 研究经ｐｔｓＡ５８Ｈ质粒转化的人胚肌腱细胞的生物学特性,探讨细胞生长特性与体外培养条件改变的关系,方法 取人胚肌腱细胞和经ｐｔｓＡ５８Ｈ质粒转化的人胚肌腱细胞,进行体外培养,对细胞进行形态学,超微结构及一般特征的观察。在不同培养条件下进行生长曲线绘制,平板克隆实验和软琼脂培养以及免疫组织化学法胶原染色,结果 在正常培养条件下,人胚肌腱细胞和转经人胚肌腱细胞的生长性状几乎无差异,且冻存复苏并不     

骨髓间充质干细胞向神经细胞定向分化的体外研究

目的　探讨骨髓间充质干细胞( marrow stromal stem cells,MSCs)向神经细胞定向分化中神经蛋白分子的表达情况。　方法　取第5～7代体外培养Wistar大鼠MSCs,以0 .5μmol/ L全反式视黄酸( all- trans retinoidacid,ATRA)预诱导2 4 h后,换用改良神经细胞培养基( modified neuronal medium,MNM)继续培养。在ATRA作用2 4 h及MNM作用2、6、9、18及36 h,免疫组织化学检测巢蛋白( Nestin)、神经元特异性核心抗原( neuron- specificnuclear protein,Neu N)、微管相关蛋白2 ( microtubule- associated protein 2 ,MAP- 2 )和胶质纤维酸性蛋白的表达情况。　结果　ATRA和MNM作用后,MSCs呈典型神经元样,伸出较多的突起和分支,形成网络。Nestin最先表达,ATRA作用2 4 h出现,Neu N其次,MNM作用2 h检测到,MAP- 2最晚,MNM作用9h检测到。Nestin在MNM作用18h后表达最强,其阳性率为92 .3%±3.4 % ;36 h后表达明显减弱,阳性率仅为12 .3%±3.4 % ,而其它标志蛋白则持续表达。　结论　ATRA和MNM能促进MSCs向神经前体细胞和神经元转化,神经蛋白分子的表达顺序与神经细胞发育过程一致,为研究神经细胞发育提供了一个较好的体外模型     

成骨细胞与血管内皮细胞联合培养的生物学特性

目的探讨成骨细胞与血管内皮细胞联合培养的生物学特性. 方法取2周龄乳兔颅盖骨及肾脏皮质传代培养制备成骨细胞(A组)、血管内皮细胞(B组)及成骨细胞与血管内皮细胞联合培养(C组),用Ⅰ型胶原和血管Ⅷ因子免疫细胞化学染色鉴定成骨细胞和血管内皮细胞,倒置相差显微镜和组织学染色观察细胞的生长特性和细胞相容性,检测碱性磷酸酶 (alkaline phosphatase,ALP)活性,观察血管内皮细胞对成骨细胞产生的ALP活性有无影响,MTT法检测细胞活力,分析细胞生长和增殖情况. 结果免疫细胞化学染色证实,培养的细胞为成骨细胞和血管内皮细胞.倒置相差显微镜、HE和Masson染色均显示两种细胞混合生长良好.ALP检测结果:C组ALP活性明显高于A组和B组(P＜0.01),A组高于B组(P＜0.05).MTT检测结果表明:C组细胞早期增殖较慢,而后期增殖较快. 结论成骨细胞与血管内皮细胞具有良好的相容性,血管内皮细胞能够增强成骨细胞的ALP活性,提高成骨细胞的增殖能力.联合培养细胞具有很强的增殖潜能.     

人脂肪组织来源的基质细胞分化为神经元样细胞的体外研究

目的 探讨人脂肪组织来源的基质细胞（adipose tissue-derived stromal cells，ADSCs）向神经元样细胞分化的可能性，为神经移植探索新的细胞来源。方法 采用胶原酶消化法分离培养成人的ADSCs，含血清的培养基进行培养，胰蛋白酶消化传代，采用第3～9代的ADSCs进行诱导。应用异丁基甲基黄嘌呤、消炎痛、胰岛素和地塞米松，诱导其向神经元样细胞和脂肪细胞分化，采用苏丹黑B和免疫细胞化学方法对ADSCs进行鉴定。结果 成功培养出ADSCs来源的基质细胞，细胞在体外生长形态类似成纤维细胞，可维持在未分化状态并稳定增殖，体外扩增可达20代。细胞表达波形蛋白和巢蛋白，大部分细胞还表达平滑肌肌动蛋白和βⅢ管蛋白；应用异丁基甲基黄嘌呤、消炎痛、胰岛素和地塞米松，可诱导ADSCs向神经元样细胞和脂肪细胞分化，其中0．1％～0．2％的细胞分化为神经元样细胞，40％～50％分化为脂肪细胞。分化的神经元样细胞具有典型的神经元形态，并能表达神经元标志物；部分分化的神经元样细胞仍然表达平滑肌肌动蛋白。结论 脂肪组织中存在能分化为神经元样细胞的基质细胞，并能克服间充质细胞的限制，分化为神经元样细胞，但这种细胞是否为有功能的神经元，还需深入研究。     

小鼠骨髓基质干细胞与人耳脱细胞软骨复合培养的研究

目的探讨以小鼠骨髓基质干细胞(MSCs)作为组织工程软骨的种子细胞,在人耳脱细胞软骨支架上生长的可行性.方法将人耳软骨经脱细胞处理,得到脱细胞软骨支架.抽取鼠的骨髓,经离心得到单个核细胞,进行体外分离培养得到MSCs.将鼠的第2代MSCs种植于脱细胞软骨支架上,体外立体培养10天,在光镜及电镜下观察细胞生长及胶原纤维排列情况.结果 MSCs在人耳脱细胞软骨支架上能立体培养成活,细胞分布不均,靠近培养液的一面细胞分布较多,其中大部分细胞进入已脱细胞的软骨陷窝内,每个陷窝内的细胞数为1～2个.结论以鼠MSCs为种子细胞,可在人耳脱细胞软骨支架上良好生长,构建组织工程软骨.     

成骨细胞与诱导剂对骨髓基质干细胞的增殖与成骨分化的影响

目的探索一种新的骨髓基质干细胞(marrow stromal stem cells,MSCs)增殖与成骨分化的体外诱导培养体系. 方法乳大鼠颅骨来源的第3代成骨细胞与诱导剂(1 nmol/L地塞米松、10 mmol/L β-甘油磷酸钠、50μg/ml抗坏血酸)对大鼠股骨、胫骨来源的MSCs生长的影响.于8块24孔板上培养MSCs,每孔接种5×104个第3代MSCs.按培养成分不同分为4组,每组2块.DMEM培养为对照组;诱导剂培养为诱导剂组;成骨细胞培养为成骨细胞组;联合使用成骨细胞与诱导剂培养为联合诱导组.计数诱导1～8 d各组MSCs的数量并绘制细胞生长曲线,检测诱导10 d的MSCs的碱性磷酸酶活性,采用RT PCR检测诱导2周时MSCs骨钙素mRNA的表达水平.结果原代及传代MSCs形态正常.细胞生长曲线示MSCs数量均随时间延长增加.成骨细胞组增殖最快,诱导剂组增殖最慢,5～8 d成骨细胞组及诱导剂组细胞数量与对照组比较,差异有统计学意义(P＜0.05).联合诱导组碱性磷酸酶活性为2.01±0.56 U与对照组0.68±0.14 U、诱导剂组1.27±0.43 U及成骨细胞组0.77±0.19 U比较,差异均有统计学意义(P＜0.05).对照组不表达骨钙素mRNA,诱导剂组为0.783±0.094、联合诱导组为0.814±0.071与成骨细胞组0.302±0.026比较,差异均有统计学意义(P＜0.05).结论联合使用成骨细胞和诱导剂诱导MSCs,不影响MSCs的正常增殖而促进MSCs的成骨分化,诱导效果较好,可望成为一种新的骨组织工程种子细胞的体外培养体系.