静电纺丝制备肌腱组织工程支架的研究进展

目的综述静电纺丝(简称电纺)技术在肌腱组织工程支架制备方面的应用,描述其应用效果及前景。方法查阅近年来国内外应用电纺技术制备肌腱组织工程支架的相关文献,并从多方面进行阐述。结果电纺技术制得的电纺纤维,因其大比表面积和高孔隙率,近年来广泛用于肌腱组织工程支架材料的研究。包括聚乳酸在内的多种材料已成功电纺成各种类型的肌腱组织工程支架,并在肌腱缺损修复中取得良好效果。结论电纺技术为肌腱组织工程支架材料的制备提供了新途径,随着该技术的完善,其将会在肌腱组织工程领域拥有广阔的应用前景。     

合成聚合支架材料在泌尿系统组织工程重建中的应用

组织工程为泌尿系统修复重建提供了一种新途径。合成聚合材料是最早应用于泌尿系统组织工程重建的支架材料。早期应用橡胶管、硅胶管等,效果不佳。之后,伴随各类可降解大分子聚合物的应用,合成聚合支架材料在泌尿系统应用的实验研究方面取得长足进步,但仍有尿道狭窄复发、纤维化、结石形成等不足。现今,电纺丝等制备技术、材料表面修饰技术的蓬勃发展、纳米及三维支架概念的提出以及成熟,为合成聚合材料更好在泌尿系统的应用提供可能。作者就合成聚合支架材料在泌尿系统的应用进展做一综述。     

衍生肌腱支架材料的细胞相容性研究

目的 探讨衍生肌腱支架材料（tendon derivation biomaterials，TDBM）与肌腱细胞的细胞相容性及肌腱细胞在此三维支架上培养的生物学行为，为肌腱组织工程新型支架材料的应用提供依据。方法将肌腱细胞与TDBM体外复合培养，设置单纯肌腱细胞培养为对照组，进行形态学观察，并检测细胞增殖、细胞周期、细胞DNA倍体水平及肌腱细胞凋亡率。通过^3H-脯氨酸（^3H-Proline）掺入试验了解材料对肌腱细胞胶原合成的影响。结果 肌腱细胞在TDBM上呈梭形生长，TDBM组细胞第2天进入对数增长期，倍增时间为3d，而单纯肌腱细胞培养对照组倍增时间为3．75d。TDBM组与单纯肌腱细胞培养对照组比较，^3H-Proline掺入值差异无统计学意义（P〉0．05），说明细胞功能未受影响。与支架材料复合培养的肌腱细胞DNA指数为0．96，增殖指数较对照组高10．1％，提示肌腱细胞在三维胶原支架上生长速度快，增殖能力强。结论TDBM具有良好的细胞相容性，可作为肌腱细胞的有效载体应用于组织工程化肌腱的构建。     

肌腱和韧带组织工程支架材料研究进展

肌腱和韧带损伤的修复治疗方法包括自体移植、异体移植和合成假体替代物的植入.组织工程肌腱和韧带作为生物性替代治疗具有其独特的优点,支架材料作为绀织工程的重要部分对肌腱和韧带的成功构建起着重要的作用.本文就近年来用于肌腱和韧带组织工程的天然和人工合成的支架材料进行综述.     

骨骼肌组织工程支架材料的研究进展

目的综述骨骼肌组织工程支架材料的研究现状,展望骨骼肌组织工程支架材料的发展方向。方法查阅近年来关于骨骼肌组织工程支架材料的相关文献,并从骨骼肌组织工程支架材料的种类、特性、制备技术、生物相容性等方面进行回顾及综合分析。结果骨骼肌组织工程支架材料种类繁多,大致可分为无机生物材料、生物可降解合成高分子材料、天然可降解生物材料和复合材料等4种,对不同特性的支架材料,制备工艺不同,制备出的支架各有其结构和功能优势,可根据不同的研究需求进行选择。结论复合材料的应用、复合支架的制备以及根据支架材料所需特定功能对其表面进行改性,是骨骼肌组织工程支架材料应用的发展方向。     

Tenomodulin在肌腱组织工程中的研究现状与展望

目的综述Tenomodulin在肌腱组织工程中的研究现状,展望其研究和应用发展方向。方法查阅近年关于Tenomodulin在肌腱组织工程中的相关研究文献,并进行分析总结。结果 Tenomodulin是一种Ⅱ型跨膜蛋白,具有调节肌腱组织发育作用,其C端具有抑制血管发生的活性作用。生物信息学特征分析Tenomodulin cDNA全长1 360 bp,定位于染色体Xq22.1上。多种细胞因子对Tenomodulin的表达具有调控作用,其中与碱性螺旋-环-螺旋转录因子Scleraxis关系最为密切;支架材料的性质、结构等对种子细胞Tenomodulin的表达也具有调控作用;应力负载和传代培养对Tenomodulin的表达具有一定影响。结论 Tenomodulin作为肌腱相对特异性标记分子,开发和利用其C端血管发生抑制作用,将在肌腱组织工程中具有重要应用潜力和前景。     

肌腱组织工程研究新进展

组织工程化肌腱原理是将分离的高浓度有活力的肌腱种子细胞种植于生物相容性好，可生物降解的细胞载体中，体外培养后植到缺损部位，形成新的、自身的，具有功能的肌腱组织，最终达到生物学意义上的完全修复。现就肌腱组织工程中肌腱细胞的特征、种子细胞来源、支架材料的制备、临床应用和面临的问题和展望等做一综述。     

生物材料改善肌腱病治疗的应用进展

肌腱病是临床常见疾病,受损伤肌腱自我修复过程缓慢,易造成胶原退变和瘢痕形成,导致局部功能障碍.生物材料具有良好的生物相容性和力学性能,近年来其作为组织工程支架及细胞和药物递送体在促进肌腱细胞再生,抑制肌腱组织炎症反应,防止肌腱周围粘连等方面显示出良好效果,被广泛应用于肌腱病相关研究中.该文对以水凝胶、静电纺丝及脱细胞支...     

胶原材料在药物缓释和组织工程中的研究进展

目的介绍胶原材料在药物缓释和组织工程中的研究新进展. 方法广泛查阅近年相关文献并进行回顾与综合分析. 结果胶原材料在药物缓释与组织工程中的应用研究已取得明显进展,胶原材料已成为组织工程研究的热点之一.一些胶原基质新型药物缓释系统和新型组织工程材料已进入临床论证阶段,将促进胶原材料在组织修复中的临床应用. 结论胶原材料在药物缓释、尤其是组织工程领域具有广阔的应用前景.除将胶原适当交联处理或与其它天然或合成高分子复合外,今后的研究中还应注重利用化学修饰改善胶原性能,通过将性质不同的支链接枝到胶原大分子上,赋予胶原新的特性,从而研制出新一代组织工程材料.     

组织工程全层皮肤研究进展

目的综述组织工程全层皮肤的研究进展,全面了解其研究现状及应用情况,为研制新型组织工程全层皮肤、改善皮肤替代物的性能奠定基础。方法广泛查阅近年来国内外组织工程全层皮肤的相关文献,并进行综合分析。结果组织工程全层皮肤在种子细胞、支架材料及构建方面均取得了一定进展,在临床应用中已经取得了一定的疗效,但移植成功率低,也不具备完整的皮肤结构,还不能完全达到临床应用的要求。结论组织工程全层皮肤是理想的皮肤替代物,发展前景很大,但在种子细胞、支架材料及构建应用等方面仍需进一步研究。     

组织工程化肌腱研究进展

对组织工程化肌腱领域中目前研究的主要成果进行综述，着重阐述了肌腱细胞外基质替代物、肌腱细胞生物学性质及肌腱细胞与细胞外基质材料复合研究中的主要问题。认为，研制适于肌腱细胞生长、粘附和发挥功能的细胞外基质材料；建立生长、增殖可调控的肌腱细胞系；在模拟体内力学条件下，进行肌腱细胞三维培养，将是研究具有特定修复功能的组织工程化肌腱的重要问题。     

Effect of cyclic three-dimensional strain on cell proliferation and collagen synthesis of fibroblast-seeded chitosan-hyaluronan hybrid polymer fiber

Background  

Tissue engineering techniques using biodegradable three-dimensional (3D) scaffolds with cultured cells offer more potential alternatives for the treatment of severe ligament and tendon injuries. In tissue engineering, one of the crucial roles of 3D scaffolds is to provide a temporary template with the biomechanical characteristics of the native extracellular matrix (ECM) until the regenerated tissue matures. The purpose of the present study was to assess the effect of various cyclic mechanical stresses on cell proliferation and ECM production in a 3D scaffold made from chitosan and hyaluronan for ligament and tendon tissue engineering.     

Möglichkeiten und Grenzen des „tissue engineering“ des vorderen Kreuzbandes

Although current concepts of cruciate ligament reconstruction using tendon transplants provide midterm knee joint stabilization, a single-bundle or double-bundle tendon cannot adequately restore the complex three-dimensional structure of the anterior cruciate ligament. Therefore, researchers are attempting to develop alternatives using tissue engineering technology. The basic principle includes seeding of suitable cells on a resorbable carrier construct, in vitro biological and mechanical stimulation to generate a ligament-like extracellular matrix, and subsequent implantation as a cruciate ligament bioprosthesis. Several natural and synthetic materials have proven to be suitable as cell carriers; however, most of these exhibit inadequate tensile strength as well as minor fatigue properties, making an additional load carrier necessary. In principle, research has shown that tissue engineering technology is capable of generating a construct with a ligament-like extracellular matrix. However, the step from basic research to clinical application has not yet been taken.     

Tendon tissue engineering and gene transfer: the future of surgical treatment

Technologic improvements in the field of tissue engineering are leading to new potential developments in the currently used approaches to treat tendon injuries including difficult clinical scenarios such as zone II flexor tendon injuries of the hand and the mutilated hand with extensive tendon defects. A combination of mesenchymal (adult stem) cells, growth factors, and bioresorbable polymers can provide a solution for the treatment of difficult tendon injuries. Extensive research is needed to show that the extracellular matrix produced in response to the cell/growth factor/polymer composites in vivo is effective and functional as a regenerate tissue. Further exciting advances are foreseen in cell-based genetic engineering with the transfer of DNA to the site of tendon lacerations. These treatment modalities require improved safety precautions to reduce the risks and enhance the benefits of gene therapy.     

碱性成纤维细胞生长因子对成骨细胞粘附特性影响的实验研究

目的 针对骨组织工程中成骨细胞与基质材料间促粘附问题,研究碱性成纤维细胞生长因子（ｂＦＧＦ）对成骨细胞粘附特性的影响。方法 取兔骨髓基质干细胞来源的成骨细胞体外培养,分别用５、１０、５０、１００及２００ｎｇ／ｍｌ浓度的ｂＦＧＦ诱导培养２４小时作为实验组;不含ｂＦＧＦ的培养基作为对照组。观察接种后０．５、１、２、４、及８小时各时间点成骨细胞粘附情况,体现学计量粘附细胞数量。结果 １０ｎｇ／ｍｌｂＦＧ     

肌腱损伤缝接处置入碱性成纤维细胞生长因子复合缓释降解膜的研究

目的研究碱性成纤维细胞生长因子(bFGF)复合缓释降解膜对减轻或防止肌腱粘连形成的作用. 方法用bFGF和能促进胶原纤维合成的试剂制成bFGF复合缓释降解膜.选取66只SD大鼠随机分成3组,每组22只,将左肢跟腱切断缝接.A组:切断缝接处包裹bFGF复合缓释降解膜;B组:切断缝接处只包裹单纯的降解膜;C组:切断缝接处不加任何处理.术后90天,对标本进行光镜、电镜、图像分析观察,羟脯氨酸(HYP)含量、腱周粘连定量测定,及生物力学测试. 结果 A组肌腱缝合段内的成纤维细胞和胶原纤维明显较其腱周结缔组织和B、C两组缝合段的数量多,差异有统计学意义(P＜0.05); HYP含量和最大抗拉强度均明显高于B、C两组,差异有统计学意义(P＜0.01).A组肌腱缝合段外周几乎保持原有的腱旁疏松结缔组织,与腱周分界清楚;而B、C两组肌腱缝合段外周的腱旁组织几乎均变成较致密的结缔组织,并长入腱内,与腱周分界不清.腱周粘连定量测定结果显示:A组腱周粘连程度远较B、C两组轻. 结论 bFGF复合缓释降解膜,可使损伤肌腱内部愈合快于腱周结缔组织增生,有减轻或防止粘连形成的作用.     

Degradation and remodeling of small intestinal submucosa in canine Achilles tendon repair

BACKGROUND: Extracellular matrix derived from porcine small intestinal submucosa is used for the repair of musculotendinous tissues. Preclinical evaluation and clinical use have suggested that small intestinal submucosa extracellular matrix degrades rapidly after implantation and can be replaced by host tissue that is functionally and histologically similar to the normal tissue. METHODS: The present study analyzed the temporal degradation of a ten-layer multilaminate device of small intestinal submucosa extracellular matrix used for the repair of canine Achilles tendon and examined the corresponding histological appearance of the remodeled tissue during the course of scaffold degradation. Devices were fabricated from small intestinal submucosa extracellular matrix labeled with 14C. The amount of 14C remaining in the remodeled graft was measured by liquid scintillation counting at three, seven, fourteen, twenty-eight, sixty, and ninety days after surgery. Blood, urine, feces, and other parenchymal tissues were also harvested to determine the fate of scaffold degradation products. Tissue specimens were prepared for routine histological analysis to examine the morphology of the remodeled graft at each time-point. RESULTS: The small intestinal submucosa extracellular matrix graft degraded rapidly, with approximately 60% of the mass lost by one month after surgery, and the graft was completely resorbed by three months after surgery. The graft supported rapid cellular infiltration and host tissue ingrowth. By ninety days after surgery, the remodeled small intestinal submucosa extracellular matrix consisted of a dense collagenous tissue with organization, cellularity, and vascularity similar to that of normal tendon. CONCLUSIONS: Small intestinal submucosa extracellular matrix is rapidly degraded after implantation for the repair of a musculotendinous tissue in this canine Achilles tendon repair model and is replaced by the deposition and organization of host tissue that is histologically similar to that of normal tissue.     

Multilayer tendon slices seeded with bone marrow stromal cells: A novel composite for tendon engineering

The ideal scaffold for tendon engineering would possess the basic structure of the tendon, native extracellular matrix, and capability of cell seeding. The purpose of this study was to assess the tissue engineering potential of a novel composite consisting of a decellularized multilayer sliced tendon (MST) scaffold seeded with bone marrow stromal cells (BMSC). BMSC and infraspinatus tendons were harvested from 20 dogs. The tendons were sectioned in longitudinal slices with a thickness of 50 µm. The slices were decellularized, seeded with BMSC, and then bundled into one composite. The composite was incubated in culture media for 14 days. The resulting BMSC‐seeded MST was evaluated by qRT‐PCR and histology. The BMSC viability was assessed by a fluorescent tracking marker. Histology showed that the seeded cells aligned between the collagen fibers of the tendon slices. Analysis by qRT‐PCR showed higher tenomodulin and MMP13 expression and lower collagen type I expression in the composite than in the BMSC before seeding. BMSC labeled with fluorescent tracking marker were observed in the composite after culture. Mechanical testing showed no differences between scaffolds with or without BMSC. BMSC can survive in a MST scaffold. The increased tenomodulin expression suggests that BMSC might express a tendon phenotype in this environment. This new composite might be useful as a model of tendon tissue engineering. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 937–942, 2009     

Effect of osteogenic protein‐1 on the matrix metabolism of bovine tendon cells

Tendon rupture is a common sports injury in adults. However, the mechanical properties of repair tissue are inferior to those of normal tissue. To accelerate tendon healing, an in vivo approach using growth factors has been applied and has shown evidence for the efficacy of biological stimulation of the repair process. Recombinant human osteogenic protein‐1 (rhOP‐1) has been shown to be effective in stimulating matrix production by various connective tissues. To test the effect of rhOP‐1 on the matrix metabolism of tendon cells in vitro, bovine tendon cells were cultured in monolayer with various doses of rhOP‐1 for 7 days. The addition of rhOP‐1 to cell culture media resulted in significant increases in cell proliferation, DNA content, and the synthesis of proteoglycans (PGs) and collagen, compared to control cultures. The relative percentage of large PGs in the OP‐1 culture was higher than that in the control culture. In conclusion, we show for the first time that rhOP‐1 stimulates the proliferation of tendon cells and their ability to synthesize and accumulate PGs and collagen in their extracellular matrix. These biological properties may be used in the tissue‐engineering of tendon tissues. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:42–48, 2008     

Extracellular matrix expression of human tenocytes in three‐dimensional air–liquid and PLGA cultures compared with tendon tissue: Implications for tendon tissue engineering

Tenocyte transplantation may prove to be an approach to support healing of tendon defects. Cell–cell and cell–matrix contacts within three‐dimensional (3D) cultures may prevent tenocyte dedifferentiation observed in monolayer (2D) culture. The present study compares both neotissue formation and tenocyte extracellular matrix (ECM) expression in 2D and 3D cultures directly with that of native tendon, in order to determine optimal conditions for tendon tissue engineering. Primary human tenocytes were embedded in poly[lactic‐co‐glycolic‐acid] (PLGA)‐scaffolds and high‐density cultures. Neotissue formation was examined by hematoxyline–eosine (H&E) and immunofluorescence staining. Gene expression of ECM proteins and vascular endothelial growth factor (VEGF) was compared at days 0 (2D), 14, and 28 in 3D cultures and tendon. Histomorphology of 3D culture showed tendon‐like tissue as tenocyte cell nuclei became more elongated and ECM accumulated. Type I collagen gene expression was higher in 2D culture than in tendon and decreased in 4‐week‐old 3D cultures, whereas type III collagen was only elevated in high‐density culture compared with tendon. Decorin and COMP were reduced in 2D and increased in 3D culture almost to ex vivo level. These results suggest that the 3D high‐density or biodegradable scaffolds cultures encourage the differentiation of expanded monolayer tenocytes in vitro to tendon‐like tissue. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1170–1177, 2010