Mechanisms of multipotency of adult stem cells derived from bone marrow stroma and peripheral blood and their application for regenerative medicine

为了实现理想的生殖医学，确保干细胞的稳定供应至关重要，使用患者自己的体细胞复制器官和组织有望实现理想的治疗，而在使用ES细胞的情况下没有许多限制。从这一角度出发，我们重点研究了骨髓基质细胞的多能性，并探讨了其在生殖医学中的潜在应用。我们成功地建立了一种新的方法，通过各种生长因子、维生素和细胞外基质的培养，将这些细胞诱导分化为成骨细胞、软骨细胞、肌肉细胞和脂肪细胞等中胚层细胞，以及神经细胞等外胚层细胞和肝细胞等内胚层细胞。有趣的是，在这些诱导条件下，几乎100%地诱导神经细胞和肝细胞是可能的。这些结果表明…其次，将绿色荧光蛋白(GFP)基因导入体外具有多向分化潜能的骨髓基质细胞系，建立了稳定表达绿色荧光蛋白的细胞系。在GFP基因导入过程中，部分细胞株表现出不同程度的分化。在体外进一步检查后，将多能培养细胞接种于免疫缺陷小鼠的皮下组织、肌肉、脑、肝脏、人工创造的骨软骨缺损区和脊髓损伤部位，并随时间收集含有接种部位的组织和器官，以组织学观察移植细胞的定位和分布，结果显示，本研究新建立的小鼠骨髓基质细胞系部分表现出完全多能性，而另一些则表现出有限的多能性。因此，通过比较这些不同表型中的基因表达，正在探索与维持未分化状态有关的基因。较少

For realization of ideal reproductive medicine, it is extremely important to secure the stable supply of stem cells, and reproduction of organs and tissues using patients' own somatic cells is expected to realize ideal therapy without a number of restrictions in cases of using ES cells. From this point of view, we here focused on multipotency of bone marrow stromal cells and investigated the potential application for reproductive medicine.First, several lines of bone marrow stromal cells were established from mouse bone marrow. We successfully established a new method to induce differentiation of these cells into mesodermal cells such as osteoblasts, cartilage cells, muscle cells, and adipocytes, ectodermal cells such as nerve cells, and endodermal cells such as hepatocytes by culture with various growth factors, vitamins, and extracellular matrix. Intriguingly, it was possible to induce nerve cells and hepatocytes at almost 100% under these induction conditions. These results indicate … More d that multipotent adult stem cells were present in bone marrow stromal cells.Next, the green fluorescent protein (GFP) gene was introduced to these bone marrow stromal cell lines exhibiting multipotency in vitro and stable cell lines expressing GFP were established. During the GFP gene introduction, some cell lines showed different degrees of differentiation. After additional in vitro examination, multipotent culture cells were inoculated in the subcutaneous tissue, muscles, brain, liver, artificially created areas lacking bones and cartilages, and spinal injury sites in immunodeficient mice, and tissues and organs containing the inoculation site were collected over time to histologically examine the localization and distribution of transplanted cells.As a result, some mouse bone marrow stromal cell lines newly established in this study showed complete multipotency while others revealed limited multipotency. Therefore, exploration of genes involved in maintenance of an undifferentiated state is underway by comparing gene expression in these different phenotypes. Less