脂肪干细胞与小肠黏膜下层构建仿生骨膜的体内成骨

背景：脂肪干细胞与小肠黏膜下层两者具有良好的组织相容性,但将二者复合构建仿生骨膜修复骨缺损的效果如何尚需进一步验证。目的：探讨以小肠黏膜下层为支架材料复合成骨诱导的脂肪干细胞构建仿生骨膜,体内成骨的可行性。方法：取兔腹股沟区的脂肪分离培养脂肪干细胞经成骨诱导后,与猪小肠黏膜下层复合体外培养3周,构建仿生骨膜。将仿生骨膜埋置于裸鼠皮下,并以小肠黏膜下层复合未成骨诱导的脂肪干细胞的复合材料置于裸鼠皮下做对照。结果与结论：兔脂肪干细胞经成骨诱导后与小肠黏膜下层体外复合培养,见两者黏附良好,细胞分泌大量的细胞外基质。植入4,8,12周组织学和透射电镜观察见有大量骨组织形成,未成骨诱导材料复合物组内无成骨细胞。仿生骨膜植入体内8周免疫组织化学测试骨钙蛋白、骨桥蛋白呈阳性反应。提示仿生骨膜植入裸鼠体内后可形成具有良好血运的新生骨组织。     

脂肪干细胞与小肠黏膜下层构建仿生骨膜的体内成骨

背景:脂肪干细胞与小肠黏膜下层两者具有良好的组织相容性,但将二者复合构建仿生骨膜修复骨缺损的效果如何尚需进一步验证.目的:探讨以小肠黏膜下层为支架材料复合成骨诱导的脂肪干细胞构建仿生骨膜,体内成骨的可行性.方法:取兔腹股沟区的脂肪分离培养脂肪干细胞经成骨诱导后,与猪小肠黏膜下层复合体外培养3 周,构建仿生骨膜.将仿生骨膜埋置于裸鼠皮下,并以小肠黏膜下层复合未成骨诱导的脂肪干细胞的复合材料置于裸鼠皮下做对照.结果与结论:兔脂肪干细胞经成骨诱导后与小肠黏膜下层体外复合培养,见两者黏附良好,细胞分泌大量的细胞外基质.植入4,8,12 周组织学和透射电镜观察见有大量骨组织形成,未成骨诱导材料复合物组内无成骨细胞.仿生骨膜植入体内8 周免疫组织化学测试骨钙蛋白、骨桥蛋白呈阳性反应.提示仿生骨膜植入裸鼠体内后可形成具有良好血运的新生骨组织.     

组织工程技术仿生构建颅颌骨组织的研究

目的:探索构建组织工程化仿生骨种植体的方法流程,并制备成骨细胞-可吸收载体种植体样品,同时尝试建立组织工程化非承载骨种植体的评价方法。方法:实验于2001-05/2005-12分别在天津市口腔医院组织工程实验室和天津大学材料学院高分子材料研究所完成。①通过相分离技术制备壳聚糖/明胶三维网络多孔支架,在支架材料表面原位沉积纳米级的羟基磷灰石晶体,构筑纳米羟基磷灰石/壳聚糖/明胶仿生骨组织工程支架材料,并进行表征和性能检测。②用酶消化法和条件培养法分离、诱导培养中国小型猪成骨细胞作为组织工程种子细胞。③用静态复合共培养法体外构建2种骨组织工程种植体样品:成骨细胞-纳米羟基磷灰石/壳聚糖/明胶仿生骨种植体,成骨细胞-纳米羟基磷灰石/胶原种植体。④采用扫描电镜、透射电镜、FDA荧光、LDH、MTT等定期观测仿生骨样品中细胞形态、细胞增殖速率、碱性磷酸酶活性、矿化结节形成等指标,以比较样品的细胞增殖活性和成骨活性。结果:①成功构筑了具有良好的生物相容性和力学相容性的纳米羟基磷灰石/壳聚糖/明胶,这种材料具有适于细胞黏附与生长的(90±1)%的孔隙率,孔径为100￣300μm的微孔结构,且原位沉积的纳米羟基磷灰石晶体的粒径为50nm左右,接近与天然骨的组成。②自中国小型猪腿骨成功分离培养了成骨细胞,并在诱导培养条件下,表现出很强的增殖活力和成骨活性,适合作为实验用骨组织工程的种子细胞。③成功构建了两种成骨细胞-可吸收载体种植体样品:经检验仿生构建的小型猪成骨细胞-纳米羟基磷灰石/壳聚糖/明胶种植体具有细胞亲和性和体外成骨活性。结论:①在体外成功仿生构建了结构与活性接近天然骨的骨组织工程种植体--纳米羟基磷灰石/壳聚糖/明胶种植体。②初步建立了仿生组织工程化非承载骨种植体的评价方法,为其进一步用于体内修复颅颌骨组织损伤的深化研究提供了实验数据和科学依据。     

非诱导条件下犬骨髓基质干细胞的生物特性

背景：种子细胞的研究是组织工程众多研究领域中最重要的基础环节，骨髓基质干细胞以其诸多优点。成为理想的骨组织工程的种子细胞。 目的：观察骨髓基质干细胞在体外培养的生长特点和非诱导条件下的成骨特性。 设计：单一样本实验。单位：福建医科大学附属口腔医院种植中心。 材料：实验于2003-05／12在福建医科大学附属口腔医院中心实验室完成。骨髓基质干细胞来自4只1岁龄的杂交犬的原代～第3代传代细胞。 方法：无菌条件下在杂交犬两侧股骨大转子部做骨髓穿刺，抽取5mL肝素抗凝的骨髓，加入到含有50mL含双抗Dulbeeco’s改良的Eagle＇s培养液的离心管中分离单个核细胞，进行首次提纯获取骨髓基质干细胞单细胞，置培养箱中培养传代，培养48h后，吸除培养液，以后每3天换液1次。继续传代。采用倒置相差显微镜及苏木精一伊红染色观察骨髓基质干细胞形态；每天进行细胞计数，测定倍增时间，绘生长曲线；用钙钴法检测碱性磷酸酶；用茜素红法染色观察钙化结节生长情况。 主要观察指标：①犬骨髓基质干细胞光镜结构。②犬骨髓基质干细胞生长曲线。③成骨分化指标碱性磷酸酶及钙化结节的观察。 结果：①形态学观察表明，骨髓基质干细胞贴壁细胞呈集落生长。有成纤维样细胞外观，未加入成骨诱导剂，细胞形态发生变化。②碱性磷酸酶表达原代细胞呈强阳性，第1代细胞呈阳性，第2，3代细胞呈弱阳性。③钙沉积出现，原代细胞染色强于传代细胞。 结论：①骨髓基质干细胞在体外培养能大量扩增，具有自然向成骨细胞分化的能力，是骨组织工程理想的种子细胞。②3代内扩增的骨髓基质干细胞有成骨活性，但原代细胞传代活性优于传代后细胞。     

构建人工椎间盘组织工程支架

背景：组织工程技术的发展为已退变椎间盘功能的恢复提供了可能。 目的：综述椎间盘组织工程中支架的研究进展。 方法：由第一作者检索PubMed 数据库中1990-01-01/2012-12-31有关椎间盘组织工程中支架的文献,以“tissue engineering, intervertebral disc, scaffold”为检索词。 结果与结论：支架材料是组织工程研究中的一项重要组成部分。椎间盘纤维环支架材料有3大类,包括天然生物材料、人工合成材料及复合材料。椎间盘纤维环支架材料种类繁多,各有优缺点,尚无公认的最合适的支架材料,支架材料选择仍需进一步的实验研究。纳米级生物材料是研究发展的一个必然趋势,另外,利用仿生学原理,在模拟人椎间盘组织的过程中对支架材料进行改进同样是一个发展趋势;此外,可注射型支架同样是另一个研究热点,可注射型支架材料的选择范围主要集中在壳聚糖、Ⅱ型胶原、透明质酸、纤维蛋白、弹性蛋白、藻酸盐身上,目前将壳聚糖作为支架的研究相对较多。     

不同来源成骨细胞构建组织工程骨膜的特异性基因表达

背景:不同来源的种子细胞在体外黏附、增殖、分化的能力不同,保持生物学性状的能力不同,因而构建的组织工程产品生物活性也有所差异.目的:尝试在分子水平了解骨膜来源之成骨细胞和盖骨来源之成骨细胞在构建组织工程骨膜中的分化能力.设计、时间及地点:对比观察,于2007-07/2008-07在陕西省人民医院中心实验室完成.材料:取健康、剖腹产的人羊膜(已取得产妇及家属的同意).按照文献方法制备脱细胞生物衍生羊膜.方法:分别选用人胚骨膜成骨细胞和颅骨成骨细胞为种子细胞,接种于脱细胞生物衍生羊膜上.经过4,6.8 d的体外培养,提取总RNA,经过反转录成cDNA,采用实时定量聚合酶链反应对目的基因成骨细胞特异转录因子,成骨细胞特异基因(oslerix)以及骨钙素读取扩增循环数(cycle threshold.Ct).主要观察指标:①成骨细胞特异转录因子的表达.②成骨细胞特异基因Osterix的表达.③成骨细胞骨钙素Osteocalcin 的表达.结果:在组织工程骨膜中.骨膜成骨细胞对转录因子的表达普遍低于颅骨成骨细胞(P< 0.05).随培养时间的延长,骨膜成骨细胞和颅骨成骨细胞对Osterix的表达均出现缓慢增加,但二者之间没有明显差异.各时间段检测结果均显示颅骨成骨细胞对骨钙素的表达高于骨膜成骨细胞,其中在4,6 d差异有显著性意义(P<0.05).结论:骨膜成骨细胞与颅骨成骨细胞在与生物衍生材料接触后,仍可保持终末的分化性状.就分化能力而言,颅骨成骨细胞优于骨膜成骨细胞.生物衍生羊膜有助于骨膜成骨细胞保持分化方向.由此可见,不同来源的成骨细胞分化能力有所不同.     

体外培养骨髓基质细胞增殖和分化的相互关系

目的：建立一种简单可靠的骨髓基质细胞向成骨细胞转化的体外培养方法，探讨骨髓基质干细胞增殖和分化的相互关系。方法：实验于2003—02／12在新疆医科大学第1附属医院包虫病临床研究所细胞室完成。将兔骨髓基质细胞悬液进行体外培养，传代培养后分组：①普通培养基组传代后仍使用普通培养基培养，每3天换液1次。②条件培养基组，分5种情况，在普通培养基中培养至第3，10,20代后即分别使用条件培养基（Dulbeeco＇s改良的Eagle＇s培养基中加入地塞米松10^-7mmol／L，β-甘油磷酸钠10mmol／L，维生素C50mg／L）持续培养30d，每3天换液1次；传代后使用条件培养基持续培养30d，每3天换液1次；传代后使用条件培养基持续培养30d，每4天传代1次。形态学观察采用倒置显微镜；碱性磷酸酶染色采用偶氮偶联法；观察钙结节形成采用Von kossa＇s染色。结果：①各组细胞形态学观察结果：普通培养基组在形态上与条件培养基组细胞无明显差别。②各组细胞钙结节和碱性磷酸酶染色结果：普通培养基培养至第3，10，20代后用条件培养基及传代后用条件培养基（每3天换液）组细胞碱性磷酸酶阳性率达80％以上，表现为成骨细胞形态并形成钙结节，Von kossa＇s染色阳性；普通培养基组及传代后用条件培养基（每4天换液）组细胞的碱性磷酸酶染色为阴性，未能形成钙结节，Von kossa＇s染色阴性。结论：①贴壁筛选法是一种简单可靠的分离骨髓基质细胞的方法。②骨髓基质细胞的分化和增殖是两个对立的状态。     

组织工程牙周膜的体外构建

背景:利用牙周膜干细胞的多向分化潜能修复牙周缺损是近来研究的热点课题.目的:探讨利用可吸收生物材料冻干胶原膜和犬牙周膜干细胞在体外构建组织工程牙周膜的可行性.设计、时间及地点:单一样本观察,于2003-11/2004 10在解放军第四军医大学口腔医院组织工程实验中心完成.材料:生物膜为冻干胶原膜由解放军第四军医大学口腔医院组织工程实验中心提供.从4只1周岁犬的下颌前牙中分离培养牙周膜干细胞.方法:取第3代犬牙周膜下细胞扩增至1×107数量级,种植在冻干胶原膜的表面,形成细胞-生物材料复合物,每日更换培养液,倒置相差显微镜动态观察细胞形态和黏附生长状况,体外培养1周左右,组织做扫描电镜、透射电镜和苏木精-伊红染色,观察细胞在冻干胶原膜材料中的生长、增殖以及基质分泌情况.主要观察指标:①光镜观察细胞接种后乍长状况.②电镜和组织学观察细胞支架复合结果.结果:培养6 d后,犬牙周膜干细胞分泌的基质与支架材料形成网状结构.复合物体外培养1周,细胞黏附在生物支架上,细胞增殖和生长良好,分泌大量基质并形成纤维状结构,细胞复层生长,伸入膜的内部,增殖的细胞和分泌的基质与膜交接成一整体,复合物成为纤维网状组织,基本具备牙周膜的纤维状结构.结论:利用冻干胶原膜为支架,犬牙周膜干细胞为种子细胞,可在体外成功构建组织工程化牙周膜.     

脂肪干细胞与温敏型支架构建人工髓核的体外研究

目的评测壳聚糖基温敏型支架与诱导后脂肪干细胞的相容性及对其功能状态的影响。方法将兔脂肪干细胞体外培养3代、诱导2周,RT-PCR检测细胞内RNA表达水平,证明向髓核分化后,与制备好的支架复合,37 ℃成胶后,培养2周,行AO/PI检测细胞存活情况,并以扫描电镜观察超微结构。结果脂肪干细胞在单层诱导培养后有Ⅱ型胶原(Col Ⅱ)和蛋白聚糖(Aggrecan)表达;与支架复合后,细胞90%以上存活,复合培养2周后无去分化现象,且Col Ⅱ、Aggrecan mRNA表达水平升高(P<0-05)。结论温敏型壳聚糖支架与诱导后脂肪干细胞相容性良好,一定程度上利于干细胞表型、功能的维持与进一步分化,可作为干细胞植入的可注射性载体材料。     

体外构建组织工程骨-软骨复合组织

背景：设计一体化、具有过渡结构的双层支架材料,复合软骨细胞、骨髓间充质细胞,有利于新生的骨与软骨组织之间形成良好界面。目的：模仿自然骨一软骨基质构建复合支架,以软骨细胞和骨髓间充质干细胞为种子细胞,体外观察复合组织的成软骨及成骨能力。方法：制备明胶一硫酸软骨素一透明质酸及明胶一陶瓷化骨多孔复合支架,构建自然骨一软骨基质复合支架,复合兔软骨细胞与骨髓间充质干细胞,分未成骨诱导与成骨诱导两组培养,并进行MTT、糖胺多糖含量、碱性磷酸酶活性检测,以及苏木精一伊红染色检测。结果与结论：未成骨诱导与成骨诱导两组骨髓间充质干细胞增殖及糖胺多糖含量差异无显著性意义。未成骨诱导组碱性磷酸酶活性缓慢上升,成骨诱导组诱导后碱性磷酸酶活性迅速上升,14d时达到稳定状态。两组苏木精一伊红染色结果无明显区别,均已形成含有双层组织的类似骨一软骨样组织,其间可见未降解支架形态,但由于基质形成不完善及支架未完全降解,此种结构不成熟,细胞分布不均匀,支架内部可见散在无细胞区域。证实采用两种细胞与双层结构的支架经体外分层复合能够形成组织工程骨软骨复合组织。     

Effect of biomimetic zinc‐containing tricalcium phosphate (Zn–TCP) on the growth and osteogenic differentiation of mesenchymal stem cells

Several studies have shown the effectiveness of zinc‐tricalcium phosphate (Zn–TCP) for bone tissue engineering. In this study, marine calcareous foraminifera possessing uniform pore size distribution were hydrothermally converted to Zn–TCP. The ability of a scaffold to combine effectively with mesenchymal stem cells (MSCs) is a key tissue‐engineering aim. In order to demonstrate the osteogenic ability of MSCs with Zn–TCP, the scaffolds were cultured in an osteogenic induction medium to elicit an osteoblastic response. The physicochemical properties of Zn–TCP were characterized by XRD, FT–IR and ICP–MS. MSCs were aspirated from rat femurs and cultured for 3 days before indirectly placing four samples into each respective well. After culture for 7, 10 and 14 days, osteoblastic differentiation was evaluated using alizarin red S stain, measurement of alkaline phosphatase (ALP) levels, cell numbers and cell viability. XRD and FT–IR patterns both showed the replacement of CO₃^2– with PO₄^3–. Chemical analysis showed zinc incorporation of 5 mol%. Significant increases in cell numbers were observed at 10 and 14 days in the Zn–TCP group, while maintaining high levels of cell viability (> 90%). ALP activity in the Zn–TCP group was statistically higher at 10 days. Alizarin red S staining also showed significantly higher levels of calcium mineralization in Zn–TCP compared with the control groups. This study showed that MSCs in the presence of biomimetically derived Zn–TCP can accelerate their differentiation to osteoblasts and could potentially be useful as a scaffold for bone tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd.     

In vitro characterization of a nanostructured fibrin agarose bio‐artificial nerve substitute

Neural tissue engineering is focused on the design of novel biocompatible substitutes to repair peripheral nerve injuries. In this paper we describe a nanostructured fibrin–agarose bioartificial nerve substitute (NFABNS), based on nanostructured fibrin–agarose hydrogels (FAHs) with human adipose‐derived mesenchymal stem cells (HADMSCs). These NFABNSs were mechanically characterized and HADMSCs behaviour was evaluated using histological and ultrastructural techniques. Mechanical characterization showed that the NFABNSs were resistant, flexible and elastic, with a high deformation capability. Histological analyses carried out in vitro during 16 days revealed that the number of HADMSCs decreased over time, with a significant increase after 16 days. HADMSCs formed cell clusters and degraded the surrounding scaffold during this time; additionally, HADMSCs showed active cell proliferation and cytoskeletal remodelling, with a progressive synthesis of extracellular matrix molecules. Finally, this study demonstrated that it is possible to generate biologically active and mechanically stable tissue‐like substitutes with specific dimensions, based on the use of HADMSCs, FAHs and a nanostructure technique. However, in vivo analyses are needed to demonstrate their potential usefulness in peripheral nerve repair. Copyright © 2015 John Wiley & Sons, Ltd.     

纳米材料复合人骨髓成骨细胞培养的研究

目的　探讨纳米材料作为组织工程骨基质材料的可行性。方法　分离培养人骨髓间充质干细胞 ,诱导为成骨细胞后作为种子细胞 ,与纳米晶羟基磷灰石胶原材料体外联合培养 ,通过对复合物光镜及扫描电镜观察 ,了解细胞在材料中生长情况。结果　人骨髓间充质干细胞可以诱导为成骨细胞 ,体外复合培养 2周 ,分布于支架材料上的细胞大量分化增殖。结论　纳米晶羟基磷灰石胶原材料是一种构建组织工程骨的较好的支架材料     

人间充质干细胞成骨诱导培养后的细胞成分研究

目的了解构建组织工程化骨的人间充质干细胞(MSCs),在体外成骨诱导环境中培养2代后,成骨细胞、软骨细胞、脂肪细胞的比例。方法体外扩增培养人MSCs,然后在含地塞米松、β-甘油磷酸钠、维生素C等的培养液中诱导培养2代,进行成骨细胞、软骨细胞、脂肪细胞的鉴定。结果人MSCs体外成骨诱导培养2代后,碱性磷酸酶阳性细胞数65%,Ⅰ型胶原免疫组化阳性细胞数55%、骨钙素阳性细胞数52%,Ⅱ型胶原免疫组化染色为阴性,油红O法染色阳性细胞数2.5%。结论人MSCs体外成骨诱导培养2代后,可有约50%的成骨细胞,少量脂肪细胞形成,无成熟的软骨细胞出现。该结论可为利用间充质干细胞构建组织工程化骨提供理论参考。     

Three‐dimensional printed polycaprolactone‐based scaffolds provide an advantageous environment for osteogenic differentiation of human adipose‐derived stem cells

The capacity of bone grafts to repair critical size defects can be greatly enhanced by the delivery of mesenchymal stem cells (MSCs). Adipose tissue is considered the most effective source of MSCs (ADSCs); however, the efficiency of bone regeneration using undifferentiated ADSCs is low. Therefore, this study proposes scaffolds based on polycaprolactone (PCL), which is widely considered a suitable MSC delivery system, were used as a three‐dimensional (3D) culture environment promoting osteogenic differentiation of ADSCs. PCL scaffolds enriched with 5% tricalcium phosphate (TCP) were used. Human ADSCs were cultured in osteogenic medium both on the scaffolds and in 2D culture. Cell viability and osteogenic differentiation were tested at various time points for 42 days. The expression of RUNX2, collagen I, alkaline phosphatase, osteonectin and osteocalcin, measured by real‐time polymerase chain reaction was significantly upregulated in 3D culture. Production of osteocalcin, a specific marker of terminally differentiated osteoblasts, was significantly higher in 3D cultures than in 2D cultures, as confirmed by western blot and immunostaining, and accompanied by earlier and enhanced mineralization. Subcutaneous implantation into immunodeficient mice was used for in vivo observations. Immunohistological and micro‐computed tomography analysis revealed ADSC survival and activity toward extracellular production after 4 and 12 weeks, although heterotopic osteogenesis was not confirmed – probably resulting from insufficient availability of Ca/P ions. Additionally, TCP did not contribute to the upregulation of differentiation on the scaffolds in culture, and we postulate that the 3D architecture is a critical factor and provides a useful environment for prior‐to‐implantation osteogenic differentiation of ADSCs. Copyright © 2016 John Wiley & Sons, Ltd.     

A biomimetic scaffold for culturing limbal stem cells: a promising alternative for clinical transplantation

Limbal tissues can be cultured on various types of scaffolds to create a sheet of limbal-corneal epithelium for research as well as clinical transplantation. An optically clear, biocompatible, biomimetic scaffold would be an ideal replacement graft for transplanting limbal stem cells. In this study, we evaluated the physical and culture characteristics of the recombinant human cross-linked collagen scaffold (RHC-III scaffold) and compared it with denuded human amniotic membrane (HAM). Optical/mechanical properties and microbial susceptibility were measured for the scaffolds. With the approval of the institutional review board, 2 mm fresh human limbal tissues were cultured on 2.5 x 2.5 cm(2) scaffolds in a medium containing autologous serum in a feeder cell-free submerged system. The cultured cell systems were characterized by morphology and immunohistochemistry for putative stem cells and differentiated cell markers. The refractive index (RI) and tensile strength of the RHC-III scaffold were comparable to human cornea, with delayed in vitro degradation compared to HAM. RHC-III scaffolds were 10-fold less susceptible to microbial growth. Cultures were initiated on day 1, expanded to form a monolayer by day 3 and covered the entire growth surface in 10 days. Stratified epithelium on the scaffolds was visualized by transmission electron microscopy. The cultured cells showed p63 and ABCG2 positivity in the basal layer and were immunoreactive for cytokeratin K3 and K12 in the suprabasal layers. RHC-III scaffold supports and retains the growth and stemness of limbal stem cells, in addition to resembling human cornea; thus, it could be a good replacement scaffold for growing cells for clinical transplantation.     

In vitro chondrogenesis with lysozyme susceptible bacterial cellulose as a scaffold

A current focus of tissue engineering is the use of adult human mesenchymal stem cells (hMSCs) as an alternative to autologous chondrocytes for cartilage repair. Several natural and synthetic polymers (including cellulose) have been explored as a biomaterial scaffold for cartilage tissue engineering. While bacterial cellulose (BC) has been used in tissue engineering, its lack of degradability in vivo and high crystallinity restricts widespread applications in the field. Recently we reported the formation of a novel bacterial cellulose that is lysozyme‐susceptible and ‐degradable in vivo from metabolically engineered Gluconacetobacter xylinus. Here we report the use of this modified bacterial cellulose (MBC) for cartilage tissue engineering using hMSCs. MBC's glucosaminoglycan‐like chemistry, combined with in vivo degradability, suggested opportunities to exploit this novel polymer in cartilage tissue engineering. We have observed that, like BC, MBC scaffolds support cell attachment and proliferation. Chondrogenesis of hMSCs in the MBC scaffolds was demonstrated by real‐time RT–PCR analysis for cartilage‐specific extracellular matrix (ECM) markers (collagen type II, aggrecan and SOX9) as well as histological and immunohistochemical evaluations of cartilage‐specific ECM markers. Further, the attachment, proliferation, and differentiation of hMSCs in MBC showed unique characteristics. For example, after 4 weeks of cultivation, the spatial cell arrangement and collagen type‐II and ACAN distribution resembled those in native articular cartilage tissue, suggesting promise for these novel in vivo degradable scaffolds for chondrogenesis. Copyright © 2013 John Wiley & Sons, Ltd.     

膨体聚四氟乙烯与人脂肪干细胞的体外生物相容性

背景：膨体聚四氟乙烯多孔高分子聚合材料是临床常用的植入假体,具有良好的生物相容性,不易变形、变质,不产生炎症吸收反应,可允许细胞游走和组织向内生长。目的：观察人脂肪干细胞与膨体聚四氟乙烯材料的生物相容性。方法：将第4代人脂肪干细胞与膨体聚四氟乙烯体外复合培养,采用倒置相差显微镜观察细胞在支架上黏附、生长及增殖情况,计算细胞黏附率,MTT比色法检测细胞增殖率。结果与结论：刚接种的细胞呈圆形透亮,在支架材料表面分布均匀,细胞活性佳,3 h后大量细胞贴壁,24 h后可见少量呈短梭形的脂肪干细胞贴壁,3d首次换液,细胞清晰可见,低密度生长时呈短梭形或多角形,分布均匀,种植7 d后细胞数量明显增加,极少细胞从支架上掉落,细胞黏附率平均达95.7%,并且细胞仍保持正常的分裂增殖速度。说明膨体聚四氟乙烯材料具有良好的细胞相容性,可作为脂肪组织工程的种子。     

医用新型Mg-Li-Ca合金材料体外生物相容性及生物活性评价

背景：新型Mg-Li-Ca合金是否具有生物相容性和生物活性,目前还未被证实。目的：通过体外实验评价新型医用Mg-Li-Ca合金的组织相容性及生物活性,初步探讨其作为医用植入材料的可行性。方法：分别采用Mg-Li-Ca合金浸提液、纯Mg浸提液、AZ31B合金浸提液与α-MEM培养液培养第3代小鼠胚胎成骨细胞,培养1,3,5 d,采用MTT法检测细胞A值并计算相对增殖率;培养5,7 d,使用碱性磷酸酶试剂盒检测细胞碱性磷酸酶活性。将第3代小鼠胚胎成骨细胞与Mg-Li-Ca合金、纯Mg、AZ31B合金分别共培养于24孔板,培养1 d后扫描电镜观察材料表面黏附及增殖情况。结果与结论：Mg-Li-Ca合金、纯Mg和AZ31合金对成骨细胞的细胞毒性为Ⅰ级,无细胞毒性,且Mg-Li-Ca合金对细胞毒性明显小于纯Mg和AZ31B合金,对成骨细胞生长增殖无显著影响,呈现出良好的生物相容性。Mg-Li-Ca合金和纯Mg对成骨细胞正常合成碱性磷酸酶无影响,具有良好的生物活性;AZ31B对成骨细胞正常合成碱性磷酸酶有显著影响。成骨细胞可在Mg-Li-Ca合金、纯Mg和AZ31合金表面正常黏附生长。表明新型Mg-Li-Ca合金有望成为新型骨科植入材料。