Osugi Masashi, Katagiri Wataru, Yoshimi Ryoko, Inukai Takeharu, Hibi Hideharu, Ueda Minoru
Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine, Tsuruma-cho, Nagoya, Aichi, Japan.
Tissue Eng Part A. 2012 Jul;18(13-14):1479-89. doi: 10.1089/ten.TEA.2011.0325. Epub 2012 Jun 12.
Tissue engineering has recently become available as a treatment procedure for bone augmentation. However, this procedure has several problems, such as high capital investment and expensive cell culture, complicated safety and quality management issues regarding cell handling, and patient problems with the invasive procedure of cell collection. Moreover, it was reported that stem cells secrete many growth factors and chemokines during their cultivation, which could affect cellular characteristics and behavior. This study investigated the effect of stem-cell-cultured conditioned media on bone regeneration. Cultured conditioned media from human bone marrow-derived mesenchymal stem cells (MSC-CM) enhanced the migration, proliferation, and expression of osteogenic marker genes, such as osteocalcin and Runx2, of rat MSCs (rMSCs) in vitro. MSC-CM includes cytokines such as insulin-like growth factor-1 and vascular endothelial growth factor. In vivo, a prepared bone defect of a rat calvarial model was implanted in five different rat groups using one of the following graft materials: human MSCs/agarose (MSCs), MSC-CM/agarose (MSC-CM), Dulbecco's modified Eagle's medium without serum [DMEM(-)]/agarose [DMEM(-)], PBS/agarose (PBS), and defect only (Defect). After 4 and 8 weeks, implant sections were evaluated using microcomputed tomography (micro-CT) and histological analysis. Micro-CT analysis indicated that the MSC-CM group had a greater area of newly regenerated bone compared with the other groups (p<0.05) and histological analysis at 8 weeks indicated that the newly regenerated bone bridge almost covered the defect. Interestingly, the effects of MSC-CM were stronger than those of the MSC group. In vivo imaging and immunohistochemical staining of transgenic rats expressing green fluorescent protein also showed that migration of rMSCs to the bone defect in the MSC-CM group was greater than in the other groups. These results demonstrated that MSC-CM can regenerate bone through mobilization of endogenous stem cells. The use of stem-cell-cultured conditioned media for bone regeneration is a unique concept that utilizes paracrine factors of stem cells without cell transplantation.
组织工程学最近已成为一种用于骨增量的治疗方法。然而，该方法存在若干问题，如高资本投入和昂贵的细胞培养、与细胞处理相关的复杂安全和质量管理问题，以及细胞采集侵入性操作给患者带来的问题。此外，据报道干细胞在培养过程中会分泌多种生长因子和趋化因子，这可能会影响细胞特性和行为。本研究调查了干细胞培养条件培养基对骨再生的影响。人骨髓间充质干细胞培养的条件培养基（MSC-CM）在体外增强了大鼠间充质干细胞（rMSCs）的迁移、增殖以及成骨标记基因（如骨钙素和Runx2）的表达。MSC-CM包含胰岛素样生长因子-1和血管内皮生长因子等细胞因子。在体内，使用以下移植材料之一将制备好的大鼠颅骨模型骨缺损植入五个不同的大鼠组：人骨髓间充质干细胞/琼脂糖（MSCs）、MSC-CM/琼脂糖（MSC-CM）、无血清的杜氏改良 Eagle 培养基[DMEM(-)]/琼脂糖[DMEM(-)]、磷酸盐缓冲液/琼脂糖（PBS）以及仅缺损（Defect）。4周和8周后，使用微型计算机断层扫描（micro-CT）和组织学分析对植入切片进行评估。Micro-CT分析表明，与其他组相比，MSC-CM组新再生骨的面积更大（p<0.05），8周时的组织学分析表明新再生的骨桥几乎覆盖了缺损。有趣的是，MSC-CM的效果比MSC组更强。对表达绿色荧光蛋白的转基因大鼠进行的体内成像和免疫组织化学染色还表明，MSC-CM组中rMSCs向骨缺损处的迁移大于其他组。这些结果表明，MSC-CM可通过动员内源性干细胞来再生骨。使用干细胞培养条件培养基进行骨再生是一种独特的概念，它利用干细胞的旁分泌因子而无需进行细胞移植。
