新型组织工程椎间盘纤维环支架的制备与性能检测

背景：以组织工程技术修复退变椎间盘,目前的研究多集中在如何修复摘除的髓核组织,然而髓核组织工程方法无法完整重建椎间盘的结构和功能,所以相应的纤维环组织工程被认为是组织工程椎间盘治疗策略的主要限制因素之一。 目的：制备天然猪脱细胞脱钙骨基质明胶,并验证其作为组织工程椎间盘纤维支架的可行性。 方法：取猪股骨近端松质骨,用环钻钻取直径10 mm、内径5 mm、厚3 mm的中空环状骨,高压水枪冲洗,进行脱脂、脱钙、脱细胞等相关处理,制成环状的支架材料。对材料进行大体、组织学、光镜、扫描电镜观察,并对支架的吸水率、孔隙率、生物力学参数等进行检测。分离培养犬骨髓间充质干细胞,采用MTT法分析支架浸提液毒性。 结果与结论：支架为乳白色,中空环状,质地柔软的多孔结构。苏木精-伊红染色示组织无细胞结构残留。光镜及扫描电镜示支架孔隙均匀,孔隙相通,平均孔径为(401.4±13.1) μm,孔隙率为(62.12±1.52)%,吸水率为(409.77±11.34)%。生物力学结果示支架的弹性模量为(47.75±6.32) kPa。MTT法显示不同浓度支架浸提液与对照 DMEM 培养液吸光度值比较,差异无显著性意义(P > 0.05),支架无细胞毒性。提示猪脱细胞脱钙骨基质明胶去细胞彻底,具有良好的孔径、孔隙率及生物力学强度,并且无毒,具备良好的生物相容性,可作为组织工程椎间盘纤维环支架材料。     

可降解组织工程心肌材料聚氨酯的体外评价

背景:体外构建组织工程化心肌是当今医学领域的研究热点,支架材料的选择和设计是心肌组织工程的关键环节,但目前仍未找到理想的心肌支架材料。目的:对新型可降解材料聚氨酯进行体外评价,初步探讨其作为心肌组织工程支架的可行性。方法:以赖氨酸基二异氰酸酯为硬段,以赖氨酸为扩展链合成新型聚氨酯(PU-Lys)。在拉力机上测试材料的缝合强度和拉伸强度;在37℃,pH=7.4的磷酸盐缓冲溶液中检测聚氨酯的降解性能;采用细胞培养MTT法、细胞形态学观察方法,分析该聚氨酯的细胞毒性。结果与结论:力学性能检测得出该聚氨酯的拉伸强度为(8.1±0.1)MPa,缝合强度为(12.2±0.8)N;体外降解8周后质量损失为(13.1±0.3)%;MTT比色法结果显示细胞毒性为0~1级;细胞形态学观察显示L929细胞在聚氨酯材料浸提液中呈梭形或三角形,贴壁良好。提示此种新型解聚氨酯具有良好的力学性能和降解性,细胞相容性良好,符合组织工程心肌支架材料的应用要求。     

新型壳聚糖-胶原支架与牙周膜细胞的生物相容性

背景：目前胶原作为牙周组织工程支架材料仍具有机械强度差、降解速度快等缺点,将其与壳聚糖复合可改善上述问题。 目的：评估新型壳聚糖-胶原支架材料的体外生物相容性。 方法：通过MTT法评估100%,75%,50%,25%壳聚糖-胶原支架材料浸提液对人牙周膜细胞的毒性。选择第4-6代生长状态良好的人牙周膜细胞与壳聚糖-胶原支架共培养,观察细胞在支架上的生长情况,并检测与壳聚糖-胶原支架复合培养前后人牙周膜细胞碱性磷酸酶活性的变化。 结果与结论：新型壳聚糖-胶原支架具有双层结构,一侧表面致密,一侧表面疏松多孔。MTT法检测不同浓度材料浸提液毒性评级为0或1级。扫描电子显微镜及组织学观察可见细胞在壳聚糖-胶原支架上增殖良好,且致密层可起屏障膜作用,阻挡细胞进入支架内部;复合培养24 h后,人牙周膜细胞的碱性磷酸酶活性与复合培养前无明显差异(P > 0.05),复合培养48,72 h后人牙周膜细胞的碱性磷酸酶活性高于复合培养前(P < 0.05)。以上结果提示新型壳聚糖-胶原支架具有良好的生物相容性及屏障功能,可进一步应用于牙周组织工程的研究。     

聚L-乳酸合成新型烧伤材料的生物相容性

背景：最近有研究表明,高分子聚合物聚L-乳酸具有很好的生物相容性,可直接参与人体代谢且无任何不良反应,是一种可用作生物支架的高分子材料。目的：验证高分子聚合物聚L-乳酸的生物相容性。方法：检测胶原复合物及聚L-乳酸的吸湿性能。分别以正常HDMEM培养基、HDMEM培养基+二甲基亚砜、HDMEM培养基+胶原复合物浸提液、HDMEM培养基+聚L-乳酸浸提液培养C3H10T1/2细胞,72 h后观察细胞形态变化。MTT法检测聚L-乳酸浸提液、二甲基亚砜、胶原复合物浸提液对C3H10T1/2细胞的毒性。在兔血中分别加入生理盐水、蒸馏水、聚L-乳酸浸提液及胶原复合物浸提液,检测溶血度。通过兔耳缘静脉分别注射生理盐水、聚L-乳酸浸提液、二甲基亚砜及胶原复合物浸提液,观察过敏反应、热源反应。将胶原复合物及聚L-乳酸分别植入兔背部皮下,4周后检测血清中炎性因子白细胞介素10和白细胞介素23的水平。结果与结论：胶原复合材料单位质量和单位面积的吸湿率均明显低于聚L-乳酸材料(P < 0.05)。在聚L-乳酸浸提液中培养的C3H10T1/2细胞生长状态良好,细胞相对增殖率高,材料毒性为1级;聚L-乳酸材料溶血率较低,无过敏反应及热源反应,植入体内后的炎症反应低于胶原复合材料(P < 0.05)。证实聚L-乳酸新型皮肤烧伤支架材料具有良好的吸收伤口液体性能及生物相容性。中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

原位生长纳米羟基磷灰石晶须增强β-磷酸三钙多孔支架的生物安全性

背景：通过纳米羟基磷灰石原位生长明显提高了磷酸钙支架的强度与韧性。 目的：体外评价纳米羟基磷灰石晶须/β-磷酸三钙(nHAW/β-TCP)作为人工骨支架材料的生物相容性。 方法：急性全身毒性试验：30只小白鼠随机分为静脉实验组,腹腔实验组和对照组,分别注射浸提液及生理盐水,24,48,72 h观察动物的一般状态。溶血试验：材料浸提液与稀释人鲜血混合观察红细胞溶解情况,545 nm下检测A值计算溶血率;致敏试验：16只豚鼠随机分为实验组、阴性对照组和阳性对照组,每只豚鼠脊柱两侧皮内注射等体积nHAW/β-TCP支架材料浸提液、生理盐水及二硝基氟苯。于注射后即刻和24,48,72 h观察局部皮肤反应。细胞毒性试验：材料浸提液培养细胞进行细胞形态大体观察,采用CCK-8法观察细胞活性。 结果与结论：急性全身毒性试验：人工骨浸提液静脉及腹腔注射后不引起小鼠呼吸、进食改变或死亡,体质量稳定。溶血试验：nHAW/β-TCP的溶血率小于ISO规定的5%,可认为这种材料无溶血作用。致敏试验：豚鼠皮内注射后未出现过敏反应。细胞毒性试验：CCK-8细胞毒性试验显示不同浓度人工骨浸提液的细胞毒性为0级。提示nHAW/β-TCP复合支架不引起全身毒性反应、溶血反应和过敏反应,且无细胞毒性,生物相容性良好,符合组织工程人工骨支架材料的应用要求。     

丝蛋白应用于牙周组织工程的可行性

背景：丝蛋白是有利于表皮细胞、成纤维细胞、成骨细胞、血管内皮细胞、胶质细胞黏附和生长的一种新型生物材料。 目的：评估丝蛋白作为支架材料应用于牙周组织工程的可行性。 方法：采用组织块法培养人牙周膜细胞,将第5代细胞悬液以2×10⁷ L^-1的浓度接种到丝蛋白支架材料上复合培养,并以1%,10%,50%,100%的丝蛋白支架浸提液培养,观察人牙周膜细胞在丝蛋白上及在丝蛋白浸提液中生长状况,用MTT法测定浸提液培养人牙周膜细胞的活力。 结果与结论：扫描电镜可见人牙周膜细胞在丝蛋白支架上伸展充分,生长旺盛,不同浓度丝蛋白支架浸提液培养对人牙周膜细胞的增殖与碱性磷酸酶活性均无影响。说明丝蛋白材料具有良好的生物相容性、独特的力学性能,可作为人牙周膜细胞黏附生长的理想支架材料较好地应用于牙周组织工程中。     

脂肪源干细胞与聚丙烯网片的生物相容性研究

目的观察脂肪源干细胞(ADSCs)与聚丙烯网片的生物相容性。方法制备兔ADSCs悬液。取聚丙烯网片浸提液培养ADSCs。用四甲基偶氮唑盐(MTT)法检测细胞活力,评价支架细胞毒性。ADSCs传代扩增后,接种到聚丙烯网片支架上,体外培养1周。用扫描电子显微镜观察细胞在支架上黏附生长及增殖。结果 ADSCs在聚丙烯网片浸提液中可保持较高的增殖率(RGR)(24、48、72 h实验组细胞RGR分别为97%、96%、101%,平均RGR为103.5%),与对照组比较,差异无统计学意义(χ2=17.45,P0.05),聚丙烯网片浸提液无细胞毒性。脂肪干细胞种植于两种支架材料后生长速度快,扫描电子显微镜观察可见脂肪干细胞呈球型,并伸展形成伪足,贴附于支架材料,细胞间相互连接成团。结论聚丙烯网片支架与ADSCs具有良好的生物相容性,无细胞毒性,可作为脂肪组织工程较理想的生物支架材料。     

铁铬钼软磁合金表面镀铬后的生物相容性

背景：研究表明,铁铬钼系列软磁合金具有理想的磁性能和机械加工性能,表面镀Cr⁶⁺处理可明显增强其在口腔环境中的耐腐蚀性,但其表面镀铬后的生物安全性仍需进一步检验。目的：评价铁铬钼软磁合金表面镀铬后的生物相容性。方法：取对数生长期L-929细胞悬液,以6×10⁷ L^-1的细胞浓度接种于96孔板中,分别加入纯钛浸提液、铁铬钼软磁合金原样浸提液、铁铬钼电镀Cr⁶⁺软磁合金浸提液与聚氯乙烯浸提液培养。培养5 d后,观察细胞形态和贴壁情况,采用CCK-8法检测细胞A值,并计算各组细胞相对增殖率,评价材料细胞毒性分级。结果与结论：纯钛浸提液组细胞形态正常,贴壁生长良好,表现为无细胞毒性;铁铬钼软磁合金原样浸提液组细胞形态和生长状态均良好,偶见个别细胞溶解,培养液内出现散在红褐色颗粒,表现为无或极轻微的细胞毒性;铁铬钼镀Cr⁶⁺软磁合金浸提液组细胞生长状态良好,表现为无或极轻微的细胞毒性;聚氯乙烯浸提液组超过70%细胞固缩或溶解呈空泡状,大量细胞碎片,超过50%细胞生长抑制,表现中度以上的细胞毒性。铁铬钼电镀Cr⁶⁺软磁合金浸提液的细胞毒性为0至1级。表明镀铬的铁铬钼软磁合金具有良好的生物相容性。 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

成纤维细胞在聚羟基丁酸酯表面黏附与种植研究

可降解高分子聚合物广泛应用于组织工程,其表面的黏附特性影响细胞的种植与生长。我们研究了成纤维细胞系NIH3T3在可降解材料聚羟基丁酸酯（PHB）表面的黏附和生长。应用线性变剪切流槽研究NIH3T3细胞在材料表面的黏附力学特性,结果表明,由于在PHB表面的临界脱离剪应力较低,高密度接种时间细胞趋于聚集;在经多聚赖氨酸衣被的表面临界脱离剪应力提高,细胞铺展生长。对三维PHB多孔支架种植细胞实验表明,在PHB材料表面进行多聚赖氨酸衣被,可以有效地提高细胞种植效率。     

海藻酸钙止血敷料与临床常用3种止血敷料体外细胞毒性的比较

背景：止血敷料是作用于创伤表面与人体组织直接接触,其生物相容性是评价敷料优劣的重要指标之一,以海藻酸钙为原料的制备的止血敷料有着廉价、相容性好等优点已成为研究的热点。目的：观察海藻酸钙止血敷料的细胞毒性,并与明胶止血海绵、纳吸棉、普通纱布等材料作对比。方法：①浸提液法：以DMEM高糖培养液作为浸提介质,分别制备海藻酸钙止血敷料、明胶止血海绵、纳吸棉、普通纱布浸提液,并设置100%,75%,50%,25%,10% 5个浓度梯度;采用上述材料浸提液培养L-929小鼠成纤维细胞24 h,以含体积分数10%DMEM高糖培养液为空白对照,以含5%二甲基亚砜DMEM高糖培养液为阳性对照组,观察细胞增殖及形态变化。②直接接触法：将L-929小鼠成纤维细胞分别接种于海藻酸钙止血敷料、明胶止血海绵、纳吸棉、普通纱布上培养24 h,观察细胞形态变化。结果与结论：①浸提液法：不同浓度梯度海藻纤维止血敷料、纱布、纳吸棉浸提液的细胞毒性均为1级,符合GB/T16886/ISO10993 医疗器械生物学评价标准;100%,75%明胶止血海绵浸提液的细胞毒性为3级,严重抑制细胞增殖。②直接接触法：纱布与海藻纤维止血敷料的细胞毒性1级,纳吸棉为2级,明胶止血海绵的细胞毒性为3级。表明海藻酸钙止血敷料无细胞毒性。 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

蚕丝-聚乳酸-羟基乙酸共聚物复合编织支架的力学性能及细胞相容性

背景：与通常的合成纤维相比,蚕丝力学性能好,又具有一定的延展性,是制作组织工程韧带/肌腱的良好支架材料,但蚕丝丝素纤维降解速度缓慢,难以与组织再生速率相匹配。 目的：分析蚕丝-聚乳酸-羟基乙酸共聚物编织绳状支架的力学性能及其与骨髓间充质干细胞体外共培养的细胞相容性。 方法：通过捻拧编织蚕丝-聚乳酸-羟基乙酸共聚物细丝混合支架,并以纤维连接蛋白作表面修饰,检测支架的力学性能。将兔骨髓间充质干细胞种植在蚕丝-聚乳酸-羟基乙酸共聚物细丝混合支架上进行体外共培养,观察细胞与支架复合生长、基质形成,以及细胞与支架结合的情况。 结果与结论：蚕丝-聚乳酸-羟基乙酸共聚物混合编织支架呈乳白色,质地均匀,韧性强,为螺旋上升的绳索状,直径为2.3 mm。支架材料的最大负荷、拉伸强度、断点伸长率、弹性模量分别为(315.06±30.77) N、(75.83±7.46) MPa、(61.39±7.26)%、(213.58±23.45) MPa。扫描电镜观察显示,骨髓间充质干细胞贴附于支架表面生长,增殖良好,细胞大多呈梭形,伸出伪足匍匐于材料的表面,形态较佳,伸展良好,呈立体状生长,并分泌基质。表明蚕丝-聚乳酸-羟基乙酸共聚物编织绳状支架具有良好的机械性能及细胞相容性。     

多孔聚乙烯醇/明胶软骨组织工程支架复合材料的制备及其生物相容性

背景：以明胶为基体制备的组织工程支架材料具有良好的生物相容性和生物降解性能,但存在力学性能低,降解速率难以控制的缺陷。 目的：制备一种软骨组织工程支架材料多孔聚乙烯醇/明胶复合物,并检测其理化性能和生物相容性。 方法：采用乳化发泡法制备聚乙烯醇/明胶多孔支架,并通过电镜分析、力学测试、皮下植入实验,检测材料孔径和孔隙率、IR光谱、力学性能和生物相容性。 结果与结论：多孔材料内部呈三维网状多孔结构,孔径均匀,有相似的孔隙率61.8%,含水率44.6%,抗拉强度为(5.01±0.03) MPa,抗压强度为(1.47±0.36) MPa,有较好的力学性能,IR光谱分析表明材料内部结构均匀。皮下植入后,炎症反应逐渐减轻,囊壁逐渐变薄,并趋于稳定,提示多孔聚乙烯醇/明胶支架材料具有较好的生物相容性和力学性能。     

Electrospinning and biocompatibility evaluation of biodegradable polyurethanes based on L-lysine diisocyanate and L-lysine chain extender

A series of biodegradable polyurethanes (PUs) were synthesized using poly(ε-caprolactone) diol (PCL) to react with L-lysine ethyl ester diisocyanate (LDI) chain extend with L-lysine ethyl ester (LEE) in solution of DMF. The structure was characterized by gel permeation chromatography, 1H-NMR, Fourier transform infrared, and DSC analyses. Mechanical property testing showed that their tensile strength rose with increasing the hard segment content with a maximum tensile strength of 34.43 ± 1.73 MPa. The average mass loss for the hydrolytic degradation was only about 13 % in 56 days while this value for the enzymatic degradation was around 95 % in 30 days. The morphological and biomechanical characters of the tubular scaffolds electrospun from the as-prepared PUs were also examined. As the solution concentration was varied from 10 to 18% (w/v), the fiber diameter was progressively increased, and the scaffold tensile strength was enhanced from 2.82 ± 0.16 MPa to 7.07 ± 0.44 MPa, the suture retention strength from 2.48 ± 0.33 to 8.38 ± 0.35 N, and the burst pressure strength from 72 ± 2 to 172 ± 2 kPa, all higher than those of native blood vessels. At the same time, the L-929 mouse fibroblasts (L-929) and human umbilical vein endothelial cells were used in cytotoxicity and cell-adhesion evaluations toward the electrospun scaffolds. The level of toxicity is less than level 1, and cells were found to attach well to and remain viable on the scaffolds.     

A hybrid electrospun PU/PCL scaffold satisfied the requirements of blood vessel prosthesis in terms of mechanical properties,pore size,and biocompatibility

In this study, a novel hybrid polyurethane/polycaprolactone (PU/PCL) tubular scaffold was fabricated using the electrospinning process for blood vessel prosthesis applications. The detailed microstructure and material properties such as porosity, tensile and bust strength, contact angle, and biocompatibility were investigated and compared with those of monolithic PU and PCL scaffolds. The mechanical properties of the hybrid PU/PCL scaffold (tensile strength: 18?MPa, pressure strength: 590?mmHg) were found to be within the range needed for artificial blood vessel applications. The pore sizes of the PU/PCL scaffold ranged from 5–150?um in diameter, are sufficient enough to allow nutrient diffusion across the membrane. The reduced hydrophobic property of the PU/PCL scaffold was the result of the addition of relatively less hydrophobic PU compared with monolithic PCL scaffold. The biocompatibility of the PU/PCL scaffold was evaluated through cytotoxicity testing, and morphological observation by scanning electron microscopy and confocal microscopy using cow pulmonary artery endothelial cells and fibroblast like cells (L929).     

新型脱细胞骨基质材料的制备及理化评估

背景：传统的结构性天然骨脱细胞的方法存在许多不足之处。 目的：用新的理化方法对结构性骨块进行脱细胞处理制作新型骨支架材料的可行性,并检测其理化性能。 方法：以股骨头负重区结构性骨块为原料,高压水枪冲洗,继而利用Triton-100、脱氧胆酸钠等进行脱细胞等理化处理,制备新型脱细胞骨基质材料,并对支架进行大体、组织学、扫描电镜、Micro-CT观察、生物力学等相关检测。 结果与结论：新型脱细胞骨基质材料保留了骨的细胞外基质成分,脱细胞彻底,扫描电镜及Micro-CT观察显示支架具备三维多孔网状结构系统,具有天然骨的孔径和孔隙率;生物力学测试脱细胞组支架的弹性模量为(552.56±58.92) MPa,强度为(11.34±3.49) MPa,与新鲜骨的弹性模量及强度比较,差异无显著性意义(P > 0.05),可作为骨组织工程支架的良好载体。     

Anterior cruciate ligament regeneration using braided biodegradable scaffolds: in vitro optimization studies

The anterior cruciate ligament (ACL) is the most commonly injured intra-articular ligament of the knee, and limitations in existing reconstruction grafts have prompted an interest in tissue engineered solutions. Previously, we reported on a tissue-engineered ACL scaffold fabricated using a novel, three-dimensional braiding technology. A critical factor in determining cellular response to such a graft is material selection. The objective of this in vitro study was to optimize the braided scaffold, focusing on material composition and the identification of an appropriate polymer. The selection criteria are based on cellular response, construct degradation, and the associated mechanical properties. Three compositions of poly-alpha-hydroxyester fibers, namely polyglycolic acid (PGA), poly-L-lactic acid (PLLA), and polylactic-co-glycolic acid 82:18 (PLAGA) were examined. The effects of polymer composition on scaffold mechanical properties and degradation were evaluated in physiologically relevant solutions. Prior to culturing with primary rabbit ACL cells, scaffolds were pre-coated with fibronectin (Fn, PGA-Fn, PLAGA-Fn, PLLA-Fn), an important protein which is upregulated during ligament healing. Cell attachment and growth were examined as a function of time and polymer composition. While PGA scaffolds measured the highest tensile strength followed by PLLA and PLAGA, its rapid degradation in vitro resulted in matrix disruption and cell death over time. PLLA-based scaffolds maintained their structural integrity and exhibited superior mechanical properties over time. The response of ACL cells was found to be dependent on polymer composition, with the highest cell number measured on PLLA-Fn scaffolds. Surface modification of polymer scaffolds with Fn improved cell attachment efficiency and effected the long-term matrix production by ACL cells on PLLA and PLAGA scaffolds. Therefore based on the overall cellular response and its temporal mechanical and degradation properties in vitro, the PLLA braided scaffold pre-coated with Fn was found to be the most suitable substrate for ACL tissue engineering.     

Functional characterization of human coronary artery smooth muscle cells under cyclic mechanical strain in a degradable polyurethane scaffold

There are few synthetic elastomeric biomaterials that simultaneously provide the required biological conditioning and the ability to translate biomechanical stimuli to vascular smooth muscle cells (VSMCs). Biomechanical stresses are important physiological elements that regulate VSMC function, and polyurethane elastomers are a class of materials capable of facilitating the translation of stress induced biomechanics. In this study, human coronary artery smooth muscle cells (hCASMCs), which were seeded into a porous degradable polar/hydrophobic/ionic (D-PHI) polyurethane scaffold, were subjected to uniaxial cyclic mechanical strain (CMS) over a span of four weeks using a customized bioreactor. The distribution, proliferation and contractile protein expression of hCASMCs in the scaffold were then analyzed and compared to those grown under static conditions. Four weeks of CMS, applied to the elastomeric scaffold, resulted in statistically greater DNA mass, more cell area coverage and a better distribution of cells deeper within the scaffold construct. Furthermore, CMS samples demonstrated improved tensile mechanical properties following four weeks of culture, suggesting the generation of more extracellular matrix within the polyurethane constructs. The expression of smooth muscle α-actin, calponin and smooth muscle myosin heavy chain and the absence of Ki-67+ cells in both static and CMS cultures, throughout the 4 weeks, suggest that hCASMCs retained their contractile character on these biomaterials. The study highlights the importance of implementing physiologically-relevant biomechanical stimuli in the development of synthetic elastomeric tissue engineering scaffolds.     

ACL reconstruction using a novel hybrid scaffold composed of polyarylate fibers and collagen fibers

The objective was to perform an initial in vivo evaluation of a novel braided hybrid polyarylate and collagen fiber scaffold for the reconstruction of the anterior cruciate ligament (ACL). The braided hybrid scaffold is composed of 75% poly(desaminotyrosyl-tyrosine dodecyl dodecanedioate)(12,10), [p(DTD DD)] fibers and 25% type I bovine collagen fibers. The scaffold is designed to temporarily bear mechanical loads and gradually degrade as neoligament tissue is deposited. Scaffolds were electron beam sterilized and used to reconstruct the ACL in five Finnish Dorset crossed-bred sheep in this feasibility study. At 4 (n = 1) and 12 (n = 4) weeks post-op, scaffolds were retrieved and analyzed for cellular ingrowth and strength retention. There was extensive cell infiltration and vascularity, which increased with time. Tissue ingrowth occurred throughout the cross section in the midsubstance of the scaffolds. After 12 weeks all scaffolds were intact. Femur-scaffold-tibia complex (FSTC) explanted at 12 weeks had a yield load of 42 ± 22 N and a stiffness of 9 ± 3 N mm(-1) . All scaffolds were well tolerated in the intraarticular space and induced tissue ingrowth, including new blood vessels, fibroblasts, inflammatory cells, and newly deposited collagen, throughout the cross section of the scaffold. Tissue ingrowth is critical to the success of a degradable scaffold for ACL reconstruction. Long-term studies in a large animal model are required to determine the efficacy of these novel hybrid scaffolds for ACL reconstruction. ? 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:2913-2920, 2012.     

不同支架材料与间充质干细胞构建组织工程韧带在前交叉韧带损伤中的应用

背景：前交叉韧带是连接于股骨和胫骨之间的致密结缔组织,是能维持膝关节前向稳定性的重要结构,前交叉韧带损伤会导致膝关节前向不稳,若不及时治疗,将继发软骨、半月板等结构损伤。 目的：综述间充质干细胞与不同支架材料构建组织工程韧带在前交叉韧带损伤中的应用。 方法：应用计算机检索1950-01/2010-11 PubMed数据库相关文章,检索词“ACL,stem cells,MSC,tendon,ligament”。共检索到文献103篇,最终纳入符合标准的文献35篇。 结果与结论：应用间充质干细胞和支架构成的组织工程韧带目前已成功在动物实验中应用,间充质干细胞能明显加快韧带损伤修复,加强组织愈合的生物力学性能,但是再生组织的生物力学性能仍未达到正常肌腱水平。同时,间充质干细胞能促进移植物与骨的愈合,防止前交叉韧带重建后腱骨不愈合导致的失败。选择合适的间充质干细胞,支架,适当的机械刺激和必要的细胞因子是构建良好组织工程韧带的关键。随着组织工程科学及支架材料工程学的发展,应用间充质干细胞构建组织工程韧带不久将从实验室走向临床应用。