纳米羟基磷灰石/聚己内酯复合大鼠骨髓间充质干细胞的生物相容性

背景:纳米羟基磷灰石/聚己内酯是一种具有优良生物相容性和生物活性的典型生物复合材料.目的:分析纳米羟基磷灰石/聚己内酯电纺薄膜作为组织工程骨支架的可行性.方法:采用静电纺丝技术制备纳米羟基磷灰石/聚己内酯电纺薄膜,将其与第3代 SD 大鼠骨髓间充质干细胞复合培养,在地塞米松、β-磷酸甘油钠、维生素C成骨诱导剂诱导下,诱导骨髓间充质干细胞向成骨细胞转化.结果与结论:纳米羟基磷灰石/聚己内酯支架具有合适的微孔结构,且孔道相互贯通.①倒置显微镜观察:复合培养7 d后细胞大部分为梭形,细胞开始分裂;14 d后,细胞生长比较旺盛,数量明显增多,细胞分泌基质并黏附于支架上.②扫描电镜观察:复合培养7 d后大量细胞位于支架孔隙内生长,增殖良好,细胞大多呈梭形,双极突起,形态较佳,呈立体状生长,并分泌基质,有纤维连接蛋白生成.表明纳米羟基磷灰石/聚己内酯支架具有良好的生物相容性,是骨组织工程的良好载体.     

电纺纳米羟基磷灰石/聚酯酰胺复合支架材料的制备及其细胞相容性

背景:采用静电纺丝技术将功能性无机纳米微粒复合高分子超细纤维,形成类细胞外基质结构和功能的复合支架材料是骨组织工程支架领域一个新的研究方向。目的:通过静电纺丝法构建纳米羟基磷灰石/脂肪族聚酯酰胺复合纤维支架材料,并初步考察其细胞相容性。方法:以静电纺丝法制备纳米羟基磷灰石/脂肪族聚酯酰胺超细纤维支架材料,通过扫描电镜、原子能谱等表面形貌的物相分析,进行细胞在复合材料上的形态学观察。结果与结论:通过静电纺丝法成功制备出纳米羟基磷灰石/脂肪族聚酯酰胺超细纤维复合材料,成骨细胞直接培养于材料上呈现良好生长行为,初步证实了复合支架材料的细胞相容性。说明静电纺丝技术在构建类骨细胞外基质结构和功能的仿生复合材料方面具有独特优势,电纺超细纤维复合材料有望成为新型的骨组织工程支架。     

电纺丝聚乳酸、聚3羟基丁酸酯共聚4羟基丁酸酯和聚碳酸亚丙酯纳米纤维的制备及表面亲水性(英文)

背景:近年来聚乳酸、羟基磷灰石类复合材料支架具有良好的生物降解性和生物相容性而被广泛的研究,但是这类复合材料在增强材料界面的结合、调节材料的降解速率、改善材料的强度等方面仍不能满足理想的组织工程支架材料的要求.目的:探讨电纺丝法制备纳米纤维的结构形态及表面亲水性.方法:分别将聚乳酸、聚3羟基丁酸酯共聚4羟基丁酸酯和聚碳酸亚丙酯通过静电纺丝法制备纳米纤维膜,扫描电镜对纤维膜的结构形态进行分析,并观察在人体环境相近的磷酸盐缓冲溶液(37℃,pH 7.4)中浸泡不同时间的表面亲水性.结果与结论:通过静电纺丝技术可以将聚乳酸、聚3羟基丁酸酯共聚4羟基丁酸酯和聚碳酸亚丙酯3种材料制各成微纳米纤维结构,控制制备参数可以获得不同直径的纤维,样品随着在培养液中的浸泡时间延长,总体显示出接触角比初始降低,亲水性增强.     

不同组分电纺丝素蛋白/聚己内酯超细纤维膜与小鼠成纤维细胞的相容性

背景:近年来,静电纺丝法已被认为是一种制各纳米至亚微米级纤维组织工程支架的简便方法.目的:对3种由静电纺丝法制备的纤维膜进行生物学评价.设计、时间及地点:观察性实验,于2009 01/04在杭州师范大学临床医学院完成.材料:电纺丝素蛋白/聚己内酯超细纤维膜(SF70/PCL30,SF50/PCL50)以及丝素蛋白/聚己内酯/纳米羟基磷灰石超细纤维膜(SF50/PCL50-nHA,其中纳米羟基磷灰石含量为30%)由浙江理工大学省部共建"先进纺织材料与制备技术教育部重点实验室"制备.方法:将L929细胞以5.5×108L-1浓度接种在3种电纺超细纤维膜上进行培养.在1,3,5 h和1,4,7d时用MTT法测定细胞黏附和增殖情况,在1 d和7 d时扫描电镜观察细胞的形态.主要观察指标:L929细胞在电纺SF70/PCL30,SF50/PCL50,SF50/PCL50-nHA超细纤维膜上的黏附和增殖情况;L929细胞的形态特征.结果:相比于没有加入纳米羟基磷灰石的电纺纤维膜,电纺SF50/PCL50-nHA 超细纤维膜会较好地提高细胞在其上的黏附和增殖能力.扫描电镜观察也表明,L929细胞可以在电纺SF50/PCL5-nHA 超细纤维膜上很好地呈梭形生长,并且在其表面可以观察到丰富的绒毛和伪足,伪足与材料紧密相联.结论:3种电纺超细纤维膜特别是电纺SF50/PCL50-nHA 超细纤维膜可以很好地应用于组织再生.     

电纺丝技术制备生物活性复合纤维支架及其体外降解性

背景:聚乳酸/羟基磷灰石类复合材料支架常用的制备方法主要有冷压法、粒子沥滤法、热致相分离法等,但是在增强材料界面的结合、调节材料的降解速率、改善材料的强度等方面仍不能满足要求。目的:制备左旋聚乳酸/羟基磷灰石复合纳米纤维支架。方法:采用静电纺丝法制备聚乳酸/羟基磷灰石复合纳米纤维支架。以扫面电镜对纤维的结构形态进行分析,并观察其在PBS中浸泡不同时间的体外降解过程。结果与结论:羟基磷灰石纳米粒子与聚乳酸/基体间存在化学键合,纳米粒子使纤维直径增大且表面粗糙程度增加,这种结构将有利于细胞在纤维膜上的伸展和和繁殖。羟基磷灰石的引入,抑制了聚乳酸降解过程中的自催化作用,减缓了聚乳酸的降解速度。说明电纺丝技术制备的聚乳酸/羟基磷灰石复合支架在组织工程支架材料方面具有潜在的应用前景。     

纳米羟基磷灰石 / 壳聚糖 / 聚丙交酯支架的体外生物相容性和成骨活性简

背景：研究发现将聚丙交酯、纳米羟基磷灰石或聚丙交酯两两复合后可在一定程度上改善支架的机械性能、生物相容性和对细胞的成骨诱导分化,但离理想的骨组织工程支架材料尚有一定的距离。 目的：对比不同配比纳米羟基磷灰石/壳聚糖/聚丙交酯支架的体外生物相容性及生物活性。 方法：采用粒子沥滤法制备纳米羟基磷灰石、壳聚糖、聚丙交酯的质量比分别为10∶10∶80、10∶20∶70、20∶10∶70的复合支架。将3组复合支架与人骨髓间充质干细胞进行体外复合培养,绘制细胞在支架上的生长曲线,以RT-PCR检测细胞碱性磷酸酶活性和骨钙素的表达。 结果与结论：配比为20∶10∶70复合支架的细胞黏附率明显高于其他两复合支架组（P 〈0.01）,并且复合培养9-27 d的细胞碱性磷酸酶活性、复合培养15-27 d的骨钙素表达明显高于其他两复合支架组（P 〈0.01）,3组细胞的增殖趋势相似。说明配比为20∶10∶70的纳米羟基磷灰石/壳聚糖/聚丙交酯支架具有良好的生物相容性及骨诱导活性。     

电纺丝技术制备生物活性复合纤维支架及其体外降解性

背景：聚乳酸/羟基磷灰石类复合材料支架常用的制备方法主要有冷压法、粒子沥滤法、热致相分离法等,但是在增强材料界面的结合、调节材料的降解速率、改善材料的强度等方面仍不能满足要求。目的：制备左旋聚乳酸/羟基磷灰石复合纳米纤维支架。方法：采用静电纺丝法制备聚乳酸/羟基磷灰石复合纳米纤维支架。以扫面电镜对纤维的结构形态进行分析,并观察其在PBS中浸泡不同时间的体外降解过程。结果与结论：羟基磷灰石纳米粒子与聚乳酸/基体间存在化学键合,纳米粒子使纤维直径增大且表面粗糙程度增加,这种结构将有利于细胞在纤维膜上的伸展和和繁殖。羟基磷灰石的引入,抑制了聚乳酸降解过程中的自催化作用,减缓了聚乳酸的降解速度。说明电纺丝技术制备的聚乳酸/羟基磷灰石复合支架在组织工程支架材料方面具有潜在的应用前景。     

电纺纳米纤维可降解输尿管支架肌肉埋植的降解性能

背景:作者前期研究了电纺纳米纤维聚乳酸-羟基乙酸共聚物可降解输尿管支架材料的体外降解性能,发现80/20聚乳酸-羟基乙酸共聚物电纺纳米纤维材料在尿液中的降解时间可以满足临床需要。目的:观察80/20聚乳酸-羟基乙酸共聚物电纺纳米纤维输尿管支架的肌肉埋植降解性能。方法:采用静电纺丝法制备80/20聚乳酸-羟基乙酸共聚物纳米纤维输尿管支架,观察其在家兔脊柱旁肌肉中的降解情况。结果与结论:成功制备了电纺纳米纤维输尿管支架,扫描电镜见微观形貌良好。80/20的聚乳酸-羟基乙酸共聚物纳米纤维输尿管支架在体内降解至10周时,支架管降解至初始质量的60%左右,支架出现断裂和崩解,虽降解速度较体外降解稍慢,但其降解性能仍能够满足临床对可降解输尿管支架的需要。     

静电纺丝纳米纤维组织工程支架的研究进展

背景：静电纺丝纳米纤维具有促进细胞生长的作用。目的：描述静电纺纳米支架对细胞生长的促进作用以及静电纺纳米支架孔径大小、机械强度缺陷改进的研究进展。方法：检索数据库为CNKI数字图书馆全文、PubMed数据库2001至2011年有关静电纺丝和组织工程支架的文献。检索关键词为“组织工程,静电纺丝,支架;electrospinning,tissue engineering scaffolds,nanofiber”。结果与结论：静电纺丝纳米纤维直径、孔径大小及纤维表面对细胞生长行为有重要影响,小孔径静电纺丝纳米纤维支架不利于细胞浸润生长,且用单一电纺技术制备得到的纳米纤维支架机械性能较差,如何增加静电纺丝纳米纤维支架孔径大小以提高细胞的浸润以及提高其机械性能强度,是目前应用研究应解决的问题。     

电纺纳米纤维可降解输尿管支架肌肉埋植的降解性能

背景：作者前期研究了电纺纳米纤维聚乳酸-羟基乙酸共聚物可降解输尿管支架材料的体外降解性能,发现80/20聚乳酸-羟基乙酸共聚物电纺纳米纤维材料在尿液中的降解时间可以满足临床需要。目的：观察80/20聚乳酸-羟基乙酸共聚物电纺纳米纤维输尿管支架的肌肉埋植降解性能。方法：采用静电纺丝法制备80/20聚乳酸-羟基乙酸共聚物纳米纤维输尿管支架,观察其在家兔脊柱旁肌肉中的降解情况。结果与结论：成功制备了电纺纳米纤维输尿管支架,扫描电镜见微观形貌良好。80/20的聚乳酸-羟基乙酸共聚物纳米纤维输尿管支架在体内降解至10周时,支架管降解至初始质量的60%左右,支架出现断裂和崩解,虽降解速度较体外降解稍慢,但其降解性能仍能够满足临床对可降解输尿管支架的需要。     

A simple rocker‐induced mechanical stimulus upregulates mineralization by human osteoprogenitor cells in fibrous scaffolds

Biodegradable electrospun polycaprolactone scaffolds can be used to support bone‐forming cells and could fill a thin bony defect, such as in cleft palate. Oscillatory fluid flow has been shown to stimulate bone production in human progenitor cells in monolayer culture. The aim of this study was to examine whether bone matrix production by primary human mesenchymal stem cells from bone marrow or jaw periosteal tissue could be stimulated using oscillatory fluid flow supplied by a standard see‐saw rocker. This was investigated for cells in two‐dimensional culture and within electrospun polycaprolactone scaffolds. From day 4 of culture onwards, samples were rocked at 45 cycles/min for 1 h/day, 5 days/week (rocking group). Cell viability, calcium deposition, collagen production, alkaline phosphatase activity and vascular endothelial growth factor secretion were evaluated to assess the ability of the cells to undergo bone differentiation and induce vascularisation. Both cell types produced more mineralized tissue when subjected to rocking and supplemented with dexamethasone. Mesenchymal progenitors and primary human mesenchymal stem cells from bone marrow in three‐dimensional scaffolds upregulated mineral deposition after rocking culture as assessed by micro‐computed tomography and alizarin red staining. Interestingly, vascular endothelial growth factor secretion, which has previously been shown to be mechanically sensitive, was not altered by rocking in this system and was inhibited by dexamethasone. Rocker culture may be a cost effective, simple pretreatment for bone tissue engineering for small defects such as cleft palate.     

透明质酸改性壳聚糖-胶原-羟基磷灰石复合支架力学特性及成骨细胞的增殖（英文）

背景：组织工程中,种子细胞需依赖于细胞外基质的存在才能发挥功能。因此支架材料的选择具有重大意义。目的：制备一种新型改性壳聚糖-胶原-羟基磷灰石复合支架,优化易于细胞黏附的组织工程支架材料工艺。方法：壳聚糖与透明质酸进行交联,红外和差示扫描量热图谱检测其结构;改性壳聚糖与胶原按1：2,1：1和2：1制备3种改性壳聚糖-胶原-羟基磷灰石复合支架,将复合支架与成骨细胞MC3T3-E1联合培养,CCK-8法检测增殖,绘制生长曲线。结果与结论：透明质酸和壳聚糖以酰胺键形成交联的新化合物,孔径在50～250μm之间,孔隙率随着胶原水平、弹性模量的增加而增加,而密度则减少;增加胶原的含量在细胞联合培养初期有利于细胞对支架的黏附和增殖,但从第10天开始,3种样品中细胞数量相差不大,均出现平台期;苏木精-伊红染色发现成骨细胞在培养初期沿着支架材料内部空隙贴壁生长,随着培养天数的增加,贴壁细胞呈集落样生长,可明显看到细胞间连接。说明透明质酸改性壳聚糖/胶原/纳米羟基磷灰石复合材料可以作为骨支架材料供成骨细胞黏附、增殖,其中胶原与壳聚糖的体积比为1：1为较优配比。     

纳米羟基磷灰石/细菌纤维素复合材料及其降解物的细胞相容性评价

背景:新型复合材料纳米羟基磷灰石,细菌纤维素是一种极具应用前景的骨组织工程材料,而骨组织工程材料要求其本身及其降解产物具有良好的细胞相容性,实验在传统的MTT法评价细胞相容性的基础上,进一步应用流式细胞术的方法从DAN合成周期的角度进行评价.目的:评价新型纳米复合材料纳米羟基磷灰石/细菌纤维素及其酶降解产物的细胞相容性.方法:应用体外细胞培养法,观察纳米羟基磷灰石,细菌纤维素复合材料及其降解物对成骨细胞形态学的影响,同时采用MTT比色法评价纳米羟基磷灰石,细菌纤维素及其降解物对成骨细胞生长和增殖的影响,并尝试用流式细胞仪检测材料作用于细胞后细胞周期时相的变化,从而在分子水平上评价材料对细胞增殖的影响.结果与结论:纳米羟基磷灰石,细菌纤维素复合材料及其降解物对成骨细胞的形态无明显影响,对细胞生长和增殖无明显抑制作用.MTT细胞毒性试验显示原材料及其降解物的细胞增殖率均在80%以上,细胞毒性均为1级,材料对培养细胞无明显细胞毒性.流式细胞仪检测结果显示材料与细胞接触后能降低G_0/G_1期细胞比例,增加S,G_2/M期细胞比例,能增加成骨细胞DNA的合成,促进成骨细胞生长和组织修复.提示纳米羟基磷灰石,细菌纤维素复合材料细胞相容性良好,是一种安全的、很有应用前景的骨组织工程支架材料.     

透明质酸改性壳聚糖-胶原-羟基磷灰石复合支架力学特性及成骨细胞的增殖(英文)

背景:组织工程中,种子细胞需依赖于细胞外基质的存在才能发挥功能。因此支架材料的选择具有重大意义。目的:制备一种新型改性壳聚糖-胶原-羟基磷灰石复合支架,优化易于细胞黏附的组织工程支架材料工艺。方法:壳聚糖与透明质酸进行交联,红外和差示扫描量热图谱检测其结构;改性壳聚糖与胶原按1:2,1:1和2:1制备3种改性壳聚糖-胶原-羟基磷灰石复合支架,将复合支架与成骨细胞MC3T3-E1联合培养,CCK-8法检测增殖,绘制生长曲线。结果与结论:透明质酸和壳聚糖以酰胺键形成交联的新化合物,孔径在50～250μm之间,孔隙率随着胶原水平、弹性模量的增加而增加,而密度则减少;增加胶原的含量在细胞联合培养初期有利于细胞对支架的黏附和增殖,但从第10天开始,3种样品中细胞数量相差不大,均出现平台期;苏木精-伊红染色发现成骨细胞在培养初期沿着支架材料内部空隙贴壁生长,随着培养天数的增加,贴壁细胞呈集落样生长,可明显看到细胞间连接。说明透明质酸改性壳聚糖/胶原/纳米羟基磷灰石复合材料可以作为骨支架材料供成骨细胞黏附、增殖,其中胶原与壳聚糖的体积比为1:1为较优配比。     

以海藻酸盐及异种骨复合技术制备组织工程化骨及体内成骨(英文)

背景:海藻酸有相对温和的凝胶条件与良好的生物相容性,已广泛应用于生物组织工程.目的:采用海藻酸钠凝胶复合异种骨的方法,构建骨组织工程载体,观察载体中细胞的生物性能及体内成骨能力.方法:取2只2周龄新西兰兔的骨髓,以1 ×10~(-8)mol/L重组人骨形态发生蛋白2诱导骨髓间充质干细胞.取诱导后第2代骨髓间充质干细胞接种于1%海藻酸钠凝胶中,培养4 d苏木精-伊红染色观察凝胶中细胞形态.将第2代骨髓间充质干细胞分为单纯DMEM凝胶组和含1%海藻酸钠的DMEM凝胶组,分别培养7 d后行骨形态发生蛋白2免疫组织化学染色观察.取24只裸鼠,随机分为2组,于两侧股部肌袋中分别植入骨髓间充质干细胞,海藻酸钠凝胶/牛松质骨复合体作为实验组,骨髓间充质干细胞,牛松质骨复合体作为对照组.术后2,4周后组织学观察复合体成骨情况,图像分析系统分析各组成骨或软骨的面积百分比.结果与结论:海藻酸钠凝胶中骨髓间充质干细胞形态饱满,细胞悬浮于凝胶中,可见细胞分裂和核分裂相.单纯DMEM凝胶组和含1%海藻酸钠的DMEM凝胶组免疫组织化学观察,细胞分裂增殖正常,伸出多种形态的突起,胞核大,核仁清晰.单纯DMEM凝胶组和含1%海藻酸钠的DMEM凝胶组的骨形态发生蛋白2表达阳性率差异无显著性意义(P>0.05).扫描电镜观察海藻酸钠凝胶均匀地复合于牛松质骨微孔中,不同平面均有细胞生长.动物实验显示术后2,4周实验组和对照组的成骨或软骨的面积百分比差异有显著性意义(P<0.05).提示以海藻酸钠凝胶,牛松质骨构建骨组织工程载体,合乎组织工程载体的超结构原理,能最大限度地承载细胞,生物性能好,对骨髓间充质干细胞增殖和成骨表型及相关的生物性能无不良影响,在体内成骨效率较高.     

Characterization and osteogenic evaluation of mesoporous magnesium–calcium silicate/polycaprolactone/polybutylene succinate composite scaffolds fabricated by rapid prototyping

The properties of scaffolds for bone tissue engineering, including their biocompatibility, highly interconnected porosity, and mechanical integrity, are critical for promoting cell adhesion, proliferation, and osteoinduction. We used various physical and biological assays to obtain in vitro confirmation that the proposed composite scaffolds are potentially suitable for applications to bone tissue engineering. The proposed new composite scaffolds, which we fabricated by a rapid prototyping technique, were composed of mesoporous magnesium–calcium silicate (m_MCS), polycaprolactone (PCL), and polybutylene succinate (PBSu). We systematically evaluated the characteristics of the composite scaffolds, such as the hydrophilicity and bioactivity. We also investigated the proliferation and osteogenic differentiation of human mesenchymal stem cells (MSCs) scaffolded on the m_MCS/PCL/PBSu composite. Our results showed that, compared to the m_MCS/PCL scaffold, the m_MCS/PCL/PBSu scaffold has improved water absorption, in vitro degradability, biocompatibility, and bioactivity in simulated body fluid, while its mechanical strength is reduced. Moreover, the results of the cytotoxicity tests specified in ISO 10993-12 and ISO 10993-5 clearly indicate that the m_MCS/PCL scaffold is not toxic to cells. In addition, we obtained significant increases in initial cell attachment and improvements to the osteogenic MSC differentiation by replacing the m_MCS/PCL scaffold with the m_MCS/PCL/PBSu scaffold. Our results indicate that the m_MCS/PCL/PBSu scaffold achieves enhanced bioactivity, degradability, cytocompatibility, and osteogenesis. As such, this scaffold is a potentially promising candidate for use in stem cell-based bone tissue engineering.

A new composite scaffold consisting of mesoporous magnesium–calcium silicate (m_MCS), polycaprolactone (PCL), and polybutylene succinate (PBSu) was manufactured by a rapid prototyping technique, for stem cell-based bone tissue engineering.     

Effect of patterned electrospun hierarchical structures on alignment and differentiation of mesenchymal stem cells: Biomimicking bone

Considering the complex hierarchical structure of bone, biomimicking the micro and nano level features should be an integral part of scaffold fabrication for successful bone regeneration. We aim to biomimic the microstructure and nanostructure of bone and study the effect of physical cues on cell alignment, proliferation, and differentiation. To achieve this, we have divided the scaffolds into groups: electrospun SU‐8 nanofibers, electrospun SU‐8 nanofibers with UV treatment, and micropatterned (20 μm sized ridges and grooves) SU‐8 nanofibers by photolithography with UV treatment. Two types of culture conditions were applied: with and without osteoinduction medium. In vitro cell proliferation assays, protein estimation, alkaline phosphatase osteodifferentiation assay, live dead assay, and cell alignment studies were performed on these micropatterned nanofiber domains. Our findings show that patterned surface induced an early osteodifferentiation of mesenchymal stem cells even in absence of osteoinduction medium. An interesting similarity with the helicoidal plywood model of the bone was observed. The cells showed layering and rotation along the patterns with time. This resembles the in vivo anisotropic multilamellar bone tissue architecture thus, closely mimicking the subcellular features of bone. This might serve as a smart biomaterial surface for mesenchymal stem cell differentiation in therapeutics where the addition of external chemical factors is a challenge.     

Electrospun poly(hydroxybutyrate) scaffolds promote engraftment of human skin equivalents via macrophage M2 polarization and angiogenesis

Human dermo‐epidermal skin equivalents (DE) comprising in vitro expanded autologous keratinocytes and fibroblasts are a good option for massive burn treatment. However, the lengthy expansion time required to obtain sufficient surface to cover an extensive burn together with the challenging surgical procedure limits their clinical use. The integration of DE and biodegradable scaffolds has been proposed in an effort to enhance their mechanical properties. Here, it is shown that poly(hydroxybutyrate) electrospun scaffolds (PHB) present good biocompatibility both in vitro and in vivo and are superior to poly‐ε‐caprolactone electrospun scaffolds as a substrate for skin reconstruction. Implantation of PHB scaffolds in healthy rats polarized macrophages to an M2‐type that promoted constructive in vivo remodelling. Moreover, implantation of DE‐PHB composites in a NOD/SCID mouse xenograft model resulted in engraftment accompanied by an increase in angiogenesis that favoured the survival of the human graft. Thus, PHB scaffolds are an attractive substrate for further exploration in skin reconstruction procedures, probably due in part to their greater angiogenic and M2 macrophage polarization properties. Copyright © 2017 John Wiley & Sons, Ltd.     

成骨诱导人脐带间充质干细胞与纳米羟基磷灰石/聚酰胺66支架材料的生物相容性

背景:纳米羟基磷灰石/聚酰胺66材料有利于成骨细胞的长入和新生骨的形成、且抗弯强度、抗压强度等各项参数与正常骨组织的力学性能相接近,能满足实验动物硬组织修复的要求.目的:分析成骨诱导后人脐带间充质干细胞与纳米羟基磷灰石/聚酰胺66复合支架的生物相容性.方法:体外培养人脐带间充质干细胞,纯化增殖,成骨诱导.取成骨诱导后的第3代人脐带间充质干细胞接种于纳米羟基磷灰石/聚酰胺66支架材料上,观察细胞的生长、增殖情况及材料细胞毒性.结果与结论:成骨诱导后人脐带间充质干细胞在复合支架上生长分化良好,增殖活性不受材料影响.成骨诱导14 d内,可见碱性磷酸酶活性随着培养时间延长而逐渐增高.MTT法检测细胞无毒性.扫描电镜观察,1 d后可见细胞在支架表面附着生长;7 d后可见细胞在材料上生长良好,材料空隙有大量充填.说明纳米羟基磷灰石/聚酰胺66支架可作为骨组织工程中人脐带间充质干细胞的细胞载体,具有良好的生物相容性,能满足骨组织工程的需要.     

Effects of polyethylene glycol content on the properties of a silk fibroin/nano-hydroxyapatite/polyethylene glycol electrospun scaffold

To study the effects of polyethylene glycol (PEG) content on the mechanical properties and degradation of silk fibroin, nano-hydroxyapatite, and PEG (SF/nHAP/PEG) electrospun scaffolds, and according to the PEG ratio in the scaffold (SF : nHAP : PEG), test groups were divided as follows: PEG-0 (10 : 2), PEG-0.5 (10 : 2 : 0.5), PEG-1 (10 : 2 : 1), and PEG-2 (10 : 2 : 2). A series of tests to determine the mechanical properties, degradation rates, and osteogenic characteristics was undertaken. PEG facilitated SF degradation (PEG-1 > PEG-0.5 > PEG-0 > PEG-2), and the mass loss of the scaffolds in PEG-1 was more than 30%, while in PEG-2 it was less than 20% after 8 days (P < 0.05). The addition of PEG strengthened the mechanical properties of the scaffold (PEG-1 > PEG-2 > PEG-0.5 > PEG-0), as the Young''s modulus increased from 41.72 ± 3.40 MPa for PEG-0 to 76.12 ± 3.73 MPa for PEG-1 (P < 0.05). PEG was favorable for the osteogenic differentiation of BMSCs (PEG-0.5 > PEG-1 > PEG-2 > PEG-0). The enhancements were attributable to the increased hydrophilicity and nHAP dispersion, as well as to the secondary structure transformation of SF. The PEG content was deemed to be optimal when the SF/nHAP/PEG ratio was equal to 10 : 2 : 1.

The modification of the mechanical and degradation properties of a SF scaffold combined with PEG and nHAP is demonstrated.