Development technique of bone regeneration using Mesenchymal Stem Cell

近年来，组织工程领域的研究发展并确立了骨髓间充质干细胞(MSCs)体外培养成骨的技术。这些最新的研究已经阐明了再生的大部分特征。一般说来，它描述了一种名为组织工程的新技术，该技术涉及从分离的细胞、生物兼容的细胞和生长因子形成的结构中形成新组织的形态形成。本研究以骨髓间充质干细胞为细胞来源，以陶瓷和可吸收胶原为基质，以重组人骨形态发生蛋白-2和富血小板血浆为生长因子。为了检验体外培养骨再生的临床应用效果，我们从以下五个方面进行了研究：1)基质的发育；2)体内成骨细胞的形成；3)成骨细胞大规模培养方法的建立；4)生长因子促进骨形成的效果。5)临床应用的可能性。在基质方面，我们研究了不可吸收羟基磷灰石和一种新型的可生物降解的β-磷酸三钙(β-TcP)的成骨能力，表明β-TcP是一种理想的骨再生支架。此外，我们还发现可吸收胶原在鼻窦和自体骨中可以作为重组人骨形态发生蛋白-2的有效支架。然而，大多数关于骨形成的研究采用了二维组织形态计量学和分子生物学方法，而不是像Micro CT这样的三维空间。我们还成功地在人类临床病例中评估了松质骨的微结构。在未来几年内，我们将开展研究，以提高牙周或牙槽骨缺损的移植物的实用性，为具有可塑性的MSCs培养骨再生技术的临床应用奠定基础。

Recent studies in the field of tissue engineering have developed and established the technique of cultured bone regeneration with mesenchymal stem cells (MSCs) derived from bone marrow. Most of characteristics of the regenerat ion have been clarified by these recent studies. Generally, it have described a new technology called tissue engin eering that involves the morphogenesis of new tissue from constructs formed of isolated cells, biocompatible scaff olds and growth factors. In the present studies, we used MSCs as cell sources, ceramics and absorbable collagen as matrices, and rhBMP-2 and Platelet Rich Plasma as growth factors. In order to examine the effectiveness of cultur ed bone regeneration for clinical use, we investigated the following five things : 1) development of matrix, 2) ost eogenesis in vivo, 3) establishment of the method of larger scale of osteoblast culture, 4) the effectiveness of growth factors to improve the bone formation. 5) A possibility of clinical application in human. In regard to the matrix, we investigated the osteogenic potential of non resorbable HA and a new biodegradable β-tricalcium phosph ate (β-TCP), showing that β-TCP would be an ideal scaffolds for bone regeneration. In addition, we found that absorbable collagen would be an effective scaffold for rhBMP-2 in the sinus as well as autogenous bone. However, m ost studies regarding bone formation have adopted two dimensional histomorphometric evaluations and molecular biol ogys, not three dimensional such as micro CT. We also successfully evaluated microstructure of trabecular bone in human clinical cases. In some years from now, we are going to perform studies to improve the utility of the graft for the periodontal or alveolar defect for clinical use of technique of the cultured bone regeneration using MSCs with plasticity.