骨髓间充质干细胞在骨科组织工程中的应用

Application of bone marrow mesenchymal stem cells in orthopedic tissue engineering

学术背景:近年来许多学者从分子、生化、物理等水平对骨髓间充质干细胞成骨分化调控进行了深入研究并取得了较大的进展。虽然骨髓间充质干细胞在骨组织工程中潜力巨大,但在体外扩增和保持成骨分化能力方面仍存在许多困难。目的:综述骨髓间充质干细胞分离培养、鉴定、成骨特性、免疫学特性及在骨科组织工程中的应用检索策略:应用计算机检索PubMed、PML、OVID与万方数据库1994-01/2007-05期间与骨髓间充质干细胞应用相关文献,检索词为"bone mesenchymal stem cell,spinal injure,bone defects,disc degeneration,骨髓间充质干细胞,脊髓损伤,骨缺损,椎间盘退变"。对资料进行初审,选取关于骨髓间充质干细胞分离培养、鉴定、成骨特性及其在组织工程中的应用的相关文献,重复研究选取年代最近的文献。排除不随机及综述文献。共收集到65篇文献,入选30篇。文献评价:入选文献包含了骨髓间充质干细胞分离培养、鉴定、成骨特性、免疫学特性及在骨科组织工程中的应用等方面的研究进展。排除的文献为明显不随机的文献、综述文献和非组织工程研究。资料综合:①骨髓间充质干细胞的分离纯化方法,如贴壁筛选法、密度梯度离心法、特制培养板筛选法、免疫磁珠分离法等,现今应用较多的是数种方法相结合,以提高原代分离纯化的效率但更理想的分离纯化方法还有待于进一步的摸索。②骨髓间充质干细胞培养常用a-MEM,DMEM-HG,DMEM-LG培养基,葡萄糖浓度、种植密度、细胞因子等都对骨髓间充质干细胞的培养有一定影响。③至今尚未发现特异性抗原表型来鉴定骨髓间充质干细胞,但利用骨髓间充质干细胞的形态学及功能学的表现并通过培养过程中出现的分化表型基本可以来推断和区分它们。④骨髓间充质干细胞具有成骨成软骨及其它多向分化的潜能并且移植后无免疫排斥反应,利用这些优点可将骨髓间充质干细胞应用于骨科许多疾病的治疗。本文主要探讨其在骨、软骨缺损,脊髓损伤、椎间盘退变等方面的应用。结论:骨髓间充质干细胞的研究及其应用近年来虽已取得很大进步,但许多领域的研究尚处于探索阶段,仍有许多问题有待解决。

BACKGROUND： In recent years, many scholars make further investigations on regulating the differentiation of bone marrow mesenchymal stem cells （BMMSCs） at the levels of molecule, biochemistry and physics and great progress have been achieved. Although BMSCs are significantly potential in the bone tissue engineering, there are yet still many blocks in the amplification in vitro and the preservation of ossification and differentiation ability. OBJECTIVE： To summarize the isolation, culture, identification, ossification, and immunological performance as well as the applications of BMSCs in the field of orthopedic tissue engineering. RETRIEVE STRATEGY： The articles related to BMSCs were retrieved through PubMed, PML, OVID and Wanfang Database according the key terms of ＂bone mesenchymal stem cells, spinal injury, bone defects, intervertebral disc degeneration＂ in both Chinese and English between January 1994 and May 2007. All the articles were selected firstly and the articles containing the aspects of isolation, culture, identification and ossification as well as the applications of BMSCs in the field of bone tissue engineering, were collected. Representative and latest references were included. However, researches of the non-randomized trials and reviews were excluded. There were 65 articles met the criteria, and 30 of them were involved. LITERATURE EVALUATION： The included articles refer to the isolation, culture, identification and ossification of BMSCs, and represent the research progress of BMSCs in the field of bone tissue engineering. The resting articles were excluded due to the obviously non-randomization, reviews or non-bone tissue engineering. DATA SYNTHESIS： ①There are four dominant methods for the isolation and purification of BMMSCs, such as adherent screening method, density gradient centrifugation, specially-made cultivating board screening and magnetic bead selection method. The combination of many methods is currently applied, but ideal methods of increasing primary isolation and purification need to be found.②Three media are frequently used for the culture of BMSCs： a-MEM, DMEM-HG, DMEM-LG. Glucose density, implanting density and cytokines all make great impacts on the culture of BMSCs. ③Specific antigen phenotype has not yet been found in identifying BMSCs, but BMSCs can be inferred and distinguished by the morphology and function together with their differentiated phenotype during the process of cultivation.④With the potential of differentiating into osteoblast, chondrocyte and other types of cells, and no immunological rejection occurs after the implantation, BMSCs can be serviced in the treatment of many orthopedic diseases. This review investigates BMSCs＇ application in bone and cartilage tissues defect, spinal injury, and intervertebral disc degeneration. CONCLUSION： Although great progress has been made in recent yeas in BMSCs＇ research and its application, many fields are placed in researching stage, and many problems need to be solved.