Tantalum trabecular metal – addition of human skeletal cells to enhance bone implant interface strength and clinical application

The osteo‐regenerative properties of allograft have recently been enhanced by addition of autogenous human bone marrow stromal cells (HBMSCs). Limitations in the use of allograft have prompted the investigation of tantalum trabecular metal (TTM) as a potential alternative. TTM is already in widespread orthopaedic use, although in applications where there is poor initial stability, or when TTM is used in conjunction with bone grafting, initial implant loading may need to be limited. The aim of this study was to evaluate the osteo‐regenerative potential of TTM with HBMSCs, in direct comparison to human allograft and autograft. HBMSCs were cultured on blocks of TTM, allograft or autograft in basal and osteogenic media. Molecular profiling, confocal and scanning electron microscopy (SEM) and biochemical assays were used to characterize cell adherence, proliferation and phenotype. Mechanical testing was used to define the tensile characteristics of the constructs. HBMSCs displayed adherence and proliferation throughout TTM, evidenced by immunocytochemistry and SEM, with significant cellular ingrowth and matrix production through TTM. In contrast to cells cultured with allograft, cell proliferation assays showed significantly higher activity with TTM (p < 0.001), although molecular profiling confirmed no significant difference in expression of osteogenic genes. In contrast to acellular constructs, mechanical testing of cell–TTM constructs showed enhanced tensile characteristics, which compared favourably to cell–allograft constructs. These studies demonstrated the ability of TTM to support HBMSC growth and osteogenic differentiation comparable to allograft. Thus, TTM represents an alternative to allograft for osteo‐regenerative strategies, extending its clinical applications as a substitute for allograft. Copyright © 2012 John Wiley & Sons, Ltd.     

成人骨髓间充质干细胞体外多向分化潜能特性的研究

目的研究体外不同诱导条件下成人骨髓间充质干细胞向成骨细胞、脂肪细胞、神经细胞分化的能力。方法用细胞化学方法对诱导后的骨髓细胞进行脂肪细胞特异油红O染色；Von Kossa及改良的钙钴法进行成骨细胞鉴定；免疫组化方法检测诱导后的骨髓细胞神经元特异性烯醇化酶(NSE)、神经丝蛋白-M(NF—M)、胶质纤维酸性蛋白(GFAP)表达。结果在不同的诱导条件下，诱导后的细胞油红O染色胞浆内可见橙红色脂滴；Von Kossa染色可见细胞间布满黑色颗粒，提示有矿化基质沉积；改良钙钻法碱性磷酸酶染色胞浆呈深棕色或深黑色。免疫组化染色显示向神经细胞方向诱导后细胞NSE( )、NF—M( )、GFAP(-)。结论成人骨髓间充质干细胞在体外具有多向分化的潜能。     

骨髓间充质干细胞促进胰岛再生的作用与研究现状

背景：研究发现,骨髓间充质干细胞移植入糖尿病大鼠后能够降低其血糖。目的：综述骨髓间充质干细胞在促进胰岛再生方面的作用与研究现状。方法：应用计算机检索2003年7月至2011年12月PubMed数据库相关文章,检索词为＂bone marrow derive mesenchymal stem cell,islet cells＂,并限定文章语言种类为English。同时计算机检索2003年7月至2011年12月万方数据库相关文章,检索词为＂骨髓间充质干细胞,胰岛细胞＂,并限定文章语言种类为中文。最终纳入符合标准的文献25篇。结果与结论：目前,移植胰岛治疗糖尿病已取得良好疗效,但由于胰岛来源匮乏和异种或异体来源的胰岛引起免疫排斥反应而难以使众多糖尿患者受益。骨髓间充质干细胞取材方便,容易进行体外分离、培养和纯化,且具有多向分化潜能。若将骨髓间充质干细胞诱导分化为胰岛细胞,可望解决胰岛细胞来源和免疫排斥问题。文章对骨髓间充质干细胞分化为胰岛细胞治疗糖尿病的研究进展进行综述,并指出了存在问题和今后的研究方向。     

骨髓间充质干细胞复合异体骨修复松质骨缺损*

背景：有研究表明骨髓间充质干细胞及异体骨可促进骨缺损的修复,但骨髓间充质干细胞复合异体骨对于松质骨缺损的修复效果至今少有报道。目的：观察骨髓间充质干细胞复合异体骨修复兔松质骨缺损效果。方法：在新西兰大白兔双侧股骨外侧髁造成0.6 cm×1.2 cm 的松质骨缺损,一侧设为模型组,骨缺损处植入复合骨髓间充质干细胞的异体骨,另一侧设为对照组,单纯植入异体骨。结果与结论：植入后4,8,12周,大体观察、X 射线检查和苏木精-伊红染色观察结果显示,模型组在新骨成长方面,缺损区修复方面均优于对照组。植入后12周,模型组骨缺损区可见大量骨小梁形成及成熟的板层骨组织,骨缺损基本修复。对照组骨缺损区仅可见大量编织骨形成,骨缺损尚未得到有效修复。模型组Lane-Sandhu 法 X 射线结合组织学观察评分高于对照组(P <0.05)。生物力学检测结果显示,植入后12周,模型组股骨髁最大压力载荷、载荷/应变比值均高于对照组(P <0.05),最大应变位移较对照组低(P <0.05)。结果证实,骨髓间充质干细胞复合异体骨可有效修复兔股骨髁松质骨缺损,且修复效果明显优于单纯异体骨移植。     

A rapid method for obtaining mesenchymal stem cells and platelets from bone marrow aspirate

Mesenchymal stem cells (MSCs) and platelet‐rich plasma (PRP) are currently used alone or in combination for therapeutic applications especially for bone repair. We tested whether MSCs can be isolated from bone marrow (BM) aspirate using a commercially available kit commonly used to obtain PRP from peripheral blood (PB). Results revealed that mononuclear cells and platelets from both PB and BM could be efficiently isolated by obtaining a mononuclear and platelet rich fraction (PB‐MPRF and BM‐MPRF, respectively). Starting with comparable volumes, the number of platelets increased 1.5‐fold in BM‐MPRF compared to PB‐MPRF. The number of clonogenic cells in BM‐MPRF samples was significantly higher than whole BM samples as revealed by CFU‐F assay (54.92 ± 8.55 CFU‐F/1.5 x 10⁵ nucleated cells and 32.50 ± 12.43 CFU‐F/1.5 x 10⁵ nucleated cells, respectively). Cells isolated from BM‐MPRF after in vitro expansion fulfilled the definition of MSCs by phenotypic criteria, and differentiated along osteogenic, adipogenic and chondrogenic lineages following induction. Results showed that the kit isolated MSCs and platelets from BM aspirate. Isolated MSCs were further expanded in a laboratory and BM‐MPRF was used clinically following BM withdrawal for rapid intra‐operative cell therapy for the treatment of bone defects. Copyright © 2012 John Wiley & Sons, Ltd.     

猪骨髓间质干细胞的分离培养及分化潜能的鉴定

目的：建立猪骨髓间质干细胞(MSCs)的体外分离培养和鉴定的方法，探讨体外培养的间充质干细胞的一些生物学特点，为利用猪的实验研究提供实验基础。方法：猪的髂嵴穿刺吸取骨髓，经密度梯度离心得到骨髓单个核细胞，接种后形成单层贴壁的成纤维样的细胞。检测细胞周期，多向诱导分化鉴定分离的细胞。结果：体外培养的原代MSCs12～14d达到融合，传代后仍具有分化成骨的能力，细胞周期显示有80％的细胞处于GO／G1期。结论：体外培养猪的MSCs具有分化成骨的潜能，生长稳定，传代后仍保持未分化状态．猪骨髓间充质干细胞分离培养体系的建立为基础研究和组织工程提供了一个有价值的动物模型。     

自体骨髓间充质干细胞移植治疗急性心肌梗死临床观察

目的探讨自体骨髓间充质干细胞经冠状动脉途径移植治疗急性心肌梗死的临床疗效。方法 NYHA心功能Ⅱ～Ⅳ级且心肌存在灌注缺损、拟择期行介入治疗术的急性心肌梗死患者36例,随机分为观察组17例和对照组19例,2组介入治疗术后分别通过大腔导管于梗死相关血管内注入等量骨髓间充质干细胞和生理盐水;于介入治疗术前、术后1,3个月行24h动态心电图、静息心脏超声心动图及99mTeSPECT检查进行疗效及风险评价。结果观察组左心室舒张末期内径术后3个月时较术前和术后1个月时均明显减小（P〈0.05）,对照组手术前、后差异无统计学意义（P〉0.05）;观察组左心室射血分数术后1,3个月时均较术前和同期对照组明显增加（P〈0.05）,对照组术后3个月较术前明显增大（P〈0.05）;观察组灌注缺损面积百分比术后3个月时较术前和术后1个月时均明显减小（P〈0.05）,对照组术后3个月与术前比较差异有统计学意义（P〈0.05）;术后3个月2组左心室舒张末期内径、左心室射血分数及灌注缺损面积百分比比较差异均有统计学意义（P〈0.05）;2组恶性临床事件比较差异无统计学意义（P〉0.05）。结论自体骨髓间充质干细胞移植治疗急性心肌梗死是相对有效安全的。     

自体骨髓间充质干细胞移植治疗扩张型心肌病的临床观察

目的观察自体骨髓间充质干细胞经冠状动脉移植治疗扩张型心肌病的临床疗效。方法 38例NYHA心功能Ⅱ～Ⅳ级、心肌存在灌注缺损且左心室射血分数<40%的扩张型心肌病患者随机分为观察组18例和对照组20例,均通过冠脉动脉造影于冠状动脉内分别注入等量骨髓间充质干细胞和生理盐水。随访3个月并记录不同时期左心室射血分数、左心室舒张末期内径和心肌灌注缺损面积等指标,并通过24hHolter方法记录恶性心血管事件的发生。结果观察组术后1,3个月左心室射血分数均较术前及同期对照组明显增加(P<0.05),对照组术后3个月较术前明显增加(P<0.05);术后1个月观察组左心室舒张末期内径较术前减小(P<0.05),对照组较术前增加(P<0.05),2组差异有统计学意义(P<0.05);术后3个月时观察组左心室舒张末期内径较术前及术后1个月时均明显减少(P<0.05),对照组较术前增加(P<0.05),与1个月时比较差异无统计学意义(P>0.05),2组差异无统计学意义(P>0.05);术后3个月观察组灌注缺损面积百分比较术前及术后1个月时降低(P<0.05),对照组较术前降低(P<0.05);2组恶性临床事件差异无统计学意义(P>0.05)。结论自体骨髓间充质干细胞移植治疗扩张型心肌病安全、有效。     

Epigenetic approaches to regeneration of bone and cartilage from stem cells

Introduction: Embryonic stem cells (ESCs) or adult stem cells, especially mesenchymal stem cells (MSCs), have been intensively studied for skeletal tissue regeneration including bone and cartilage. Epigenetic mechanisms play essential roles in stem cell maintenance and differentiation. However, little is known about the epigenetic regulation of osteogenesis and chondrogenesis of stem cells.

Areas covered: In this review, features of ESCs and adult stem cells, epigenetics and chromatin structure, as well as epigenetic mechanisms, such as chromatin remodeling, DNA methylation and histone modifications, polycomb group (PcG) proteins and microRNAs are described. Epigenetic researches of stem cell are introduced.

Expert opinion: Epigenetic alterations of stem cell during the in vitro differentiation can be controlled for clinical applications. MSCs are effective resources for skeletal tissue regeneration in both undifferentiated and differentiated states. Understanding epigenetic signatures of MSC is crucial to maintain the stemness. In addition, investigation of epigenetic changes in the differentiation of MSCs is very important to develop methods or chemicals to promote efficient differentiation of MSCs. Inhibition of PcG protein enhancer of zeste (Ezh2) a chromatin modifier, could be a promising candidate to improve MSC differentiation by decreasing Ezh2-mediated H3K27me3.     

骨髓间充质干细胞增殖能力与皮质类固醇性骨坏死

背景：皮质类固醇激素性骨坏死是造成髋关节功能丧失的主要病因之一。近年研究表明,激素性股骨头坏死可能与激素引起的骨髓间充质干细胞增殖能力有关。 目的：检测皮质类固醇性骨坏死患者骨髓间充质干细胞的增殖活性,为建立自体骨髓干细胞移植治疗股骨头坏死的合理性寻求证据。 方法：选取皮质类固醇性股骨头坏死病例设为股骨头坏死组,按取材部位不同再分为股骨头坏死股骨头组、股骨头坏死髂骨组,同时选取无股骨头坏死、无激素应用的拟行人工关节置换的股骨颈骨折患者设为对照组。用密度梯度离心法分离各组骨髓间充质干细胞,再经贴壁筛选法筛选,选取第3代细胞进行实验。 结果与结论：MTT结果显示,股骨头坏死股骨头组增殖能力明显弱于其他2组,其骨髓间充质干细胞在培养后1-7d为生长滞留期,第8天达到对数生长期,以后进入到平台期,而其他2组较病例组生长曲线明显前移,并且峰值增高。流式细胞仪测定的细胞周期结果显示,股骨头坏死股骨头组中G0/G1细胞比例明显增高,而S＋G2/M期细胞比例降低,细胞增殖指数较其他2组降低（P〈0.05）,而股骨头坏死髂骨组的细胞增殖活性最强。结果证实,皮质类固醇性骨坏死患者股骨头来源的骨髓间充质干细胞增殖活性较低,髂骨来源的骨髓间充质干细胞活性增殖活性较高。     

Breaking dogmata to help patients: non-myeloablative haematopoietic stem cell transplantation

Various dogmata have been broken as a consequence of the evolution of knowledge in the area of allogeneic haematopoietic stem cell (HSC) transplantation. The following is now clear: for the successful engraftment of allogeneic HSC, bone marrow ablation of the recipient is not required; HSCs create their own space through graft-versus-host reactions; several malignancies can be eradicated by the graft-versus-tumour effect; HSC allografting can be conducted on an out-patient basis; HSC allografting can be done in aged or debilitated individuals; HSC allografting can be achieved without transfusion of blood products; and the costs of the allografting procedures can be substantially diminished. Despite the fact that HSC allografting with reduced intensity conditioning may be related to several disadvantages, such as mixed chimaerism and relapse of the malignancy, breaking these dogmata has resulted in availability of HSC allografting to a larger number of individuals worldwide, thus offering true curative therapeutic options to patients who otherwise would not qualify to be given these opportunities.     

Progenitor and stem cells for bone and cartilage regeneration

Research in regenerative medicine is developing at a significantly quick pace. Cell‐based bone and cartilage replacement is an evolving therapy aiming at the treatment of patients who suffer from limb amputation, damaged tissues and various bone and cartilage‐related disorders. Stem cells are undifferentiated cells with the capability to regenerate into one or more committed cell lineages. Stem cells isolated from multiple sources have been finding widespread use to advance the field of tissue repair. The present review gives a comprehensive overview of the developments in stem cells originating from different tissues and suggests future prospects for functional bone and cartilage tissue regeneration. Copyright © 2009 John Wiley & Sons, Ltd.     

胎儿和成人骨髓间充质千细胞体外造血支持能力的比较

胎儿出生以后,造血干细胞(HSC)才从胎儿的肝脏和脾脏转移到骨髓,这一过程可能由不同的造血微环境中的信号分子所介导.间充质干细胞(MSC)是骨髓微环境中间质细胞如成骨细胞、内皮细胞的前体祖细胞.研究者推测,胎儿出生前的骨髓可能并不特别适合HSC生长.然而,该假说尚缺乏直接的证据支持.本研究通过对胎儿和成人骨髓MSC的造血支持能力进行比较,拟为此提供证据.成人骨髓MSC来源于3位健康供者,胎儿骨髓MSC来源于孕19-20周流产的胎儿.MSC辐照后与CD34+一起进行长期培养启动细胞分析,计数克隆形成细胞的数童,流式分析培养后CD34+的表型变化.RT-PCR分析两种MSC中细胞因子的表达.结果显示,成人骨髓MSC比胎儿骨髓MSC具有更强的造血支持能力,两者都促进CD34+向髓系细胞分化,两者之间细胞因子的表达存在差异.结论:与胎儿骨髓MSC相比,成人骨髓MSC在某些治疗,尤其是促进造血恢复方面具有更广泛的应用前景.     

次声对大鼠骨髓间充质干细胞分泌存活素能力影响的研究

目的:探讨次声对骨髓间充质干细胞(BMSCs)分泌存活素(survivin)能力的影响,初步探讨次声提高BMSCs增殖活性和抑制凋亡的机制。方法:应用全骨髓培养法获取SD大鼠原代的BMSCs,培养传代,取第三代细胞分为次声干预组与空气暴露组,两组的处理时间均为60min。采用免疫荧光技术检测两组细胞存活素表达的情况。结果:次声处理组的存活素阳性细胞率(59.9±6.1),空白对照组存活素阳性细胞率(24.3±5.8),两组具有显著性差异(P<0.05)。从荧光发光强度来看次声处理组BMSC单个细胞表达存活素的荧光强度也明显大于对照组。结论:经次声作用的BMSCs在培养72h后其存活素的表达能力明显大于空气暴露组,说明次声促进BMSCs增殖、抑制其凋亡的可能机制之一为次声提高了BMSCs分泌存活素的能力。     

肝硬化干细胞移植治疗中自体骨髓采集临床研究

目的探讨肝硬化患者自体骨髓采集过程的临床表现。方法 122例行自体骨髓采集的肝硬化患者,比较采集前5min、局部麻醉、穿刺术中及术后15min患者心率、收缩压、舒张压变化;比较前3管骨髓采集中患者疼痛评分及每管抽取时间。结果以双侧髂后上嵴为骨髓采集部位,局部麻醉、穿刺及抽取骨髓过程中患者心率均高于术前（P〈0.05）,收缩压、舒张压与术前比较差异无统计学意义（P〉0.05）,术后15min收缩压、舒张压低于术前（P〈0.05）、但在正常范围,心率与术前比较差异无统计学意义（P〉0.05）;双侧局部麻醉时疼痛程度评分差异无统计学意义（P〉0.05）,右侧穿刺时疼痛程度评分高于左侧（P〈0.05）,抽取双侧第1管骨髓时疼痛程度评分高于第2,3管（P〈0.05）。结论正确掌握穿刺方法及抽取速度,可采集较高数量和质量的自体骨髓干细胞。     

BMP-2基因转染兔骨骼肌干细胞修复骨缺损实验研究

目的 探讨AdrhBMP-2修饰的兔骨骼肌干细胞(RRSMSCs)为种子细胞、脱钙骨基质(DBM)为支架材料构建组织工程化人工骨修复兔桡骨大段骨缺损的可行性。方法 建立兔桡骨干骨缺损(20mm)模型，50只新西兰兔分为5组：AdrhBMP-2转染RSMSCs／DBM组(A组)、AdGFP转染RSMSCs／DBM组(B组)、未转染RSMSCs／DBM组(C组)、单纯DBM组(D组)和对照组(E组)。术后4周和6周分别行骨密度、X线、生物力学及组织学检查。结果 术后4周，A组骨修复达到X线愈合标准，但髓腔不通；术后6周，各组的愈合率分别为A组100％、B组50%、C组33％，D组和E组为0。结论 AdrhBMP-2修饰的RSMSCs为种子细胞、DBM为支架材料构建的基因强化组织工程骨能修复兔桡骨长20mm的大段骨缺损，为临床上大范围骨缺损的修复提供了一种更为有效的方法和材料。     

骨髓间充质干细胞及其载体在股骨头坏死治疗中的研究与进展

背景：骨髓间充质干细胞作为一种多能干细胞在股骨头坏死治疗中的应用越来越多,而单纯干细胞移植及注入往往效果不佳,联合支架材料或其复合物可更好地发挥作用。 目的：综述骨髓间充质干细胞联合载体治疗股骨头坏死的临床及实验研究现状,并展望发展前景。 方法：以＂股骨头坏死、骨髓间充质干细胞、载体或支架材料;osteonecrosis of the femoral head,avascularnecrosis, bone marrow mesenchymal stem cells,carrier or scaffold material＂为检索词,应用计算机检索1989至2013年中国知网及PubMed数据库关于骨髓间充质干细胞及其载体在股骨头坏死治疗方面的临床及实验文献报道,归纳综述各种载体的特性及局限性。 结果与结论：理想的载体可促进及诱导骨髓间充质干细胞修复股骨头的能力,现有的载体种类繁多,包括自体松质骨、异体骨、天然生物材料、有机材料、生物陶瓷、纳米材料等,各有利弊。所以人们通过将材料复合的手段来寻找理想的载体和支架材料,但仍有一些问题需要深入研究与解决,如支架材料来源没有统一的生产标准、规格及公认的制作方法;如何控制及避免支架植入后的免疫反应及炎症反应;如何保证降解速率与股骨头区域的骨与软骨生成速率一致;如何全面的检测植入后的细胞毒性、生物相容性及治疗效果等。     

MRI示踪超顺磁性氧化铁标记骨髓间充质干细胞移植治疗股骨头缺血性坏死

背景：骨髓间充质干细胞移植是治疗股骨头坏死的发展方向之一。近年来,利用超顺磁性氧化铁纳米颗粒标记靶细胞再经MRI显像的方法已成为研究的焦点。目的：观察超顺磁性氧化铁标记的骨髓间充质干细胞在MRI信号上的变化情况及对兔股骨头坏死的修复效果。方法：将超顺磁性氧化铁标记的兔骨髓间充质干细胞、未标记的骨髓间充质干细胞、生理盐水采用原位移植方式移植入兔股骨头坏死区,行MRI检测,观察移植入坏死区的超顺磁性氧化铁标记的骨髓间充质干细胞在SE T2WI、FSE T2WI、GRE T2WI 三种扫描序列中信号变化情况;同时行组织学观察及高倍镜下缺损标本边缘新生骨小梁面积百分比行统计学分析。结果与结论：超顺磁性氧化铁标记的骨髓间充质干细胞原位移植侧,在SE T2WI、FSE T2WI、GRE T2＊WI 三种扫描序列中信号减低区即为实验中的靶点,MRI图像示靶点在3种扫描序列中信号强度均有不同程度的降低,而对照侧则无明显信号改变;移植后6周,超顺磁性氧化铁标记的骨髓间充质干细胞移植侧高倍镜下缺损标本边缘新生骨小梁面积百分比与未标记的骨髓间充质干细胞移植侧间差异无显著性意义（P〉0.05）,均高于生理盐水移植侧,差异有显著性意义（P〈0.01）。结果可见超顺磁性氧化铁标记的骨髓间充质干细胞与未标记的骨髓间充质干细胞原位移植治疗兔股骨头坏死有着同样的效果,MRI 可对超顺磁性氧化铁标记的骨髓间充质干细胞进行活体示踪检测。     

肝衰竭患者行自体骨髓干细胞移植的护理

目的探讨对肝衰竭自体骨髓干细胞移植患者的护理和观察对预后的影响。方法总结45例采用自体骨髓干细胞移植介入治疗慢性肝衰竭患者移植前、术中和移植后的护理与观察体会。结果45例患者手术成功率100％;多数患者临床症状和肝功能均有明显改善;术后出现2例发热、3例恶心呕吐,术后2周内1例慢性重症肝炎死亡。结论加强自体骨髓干细胞移植患者的护理和观察,可以改善患者肝功能,减少并发症,提高生存率。