ESTABLISHMENT OF FUNDAMENTAL STRATEGIES FOR SKELETAL MUSCLE TISSUE REGENERAIZON USING HEMATOPOIETIC CELLS FOR MUSCULAR DYSTROPHY DISEASE

最近，分化。在小鼠和人类的骨髓移植后，包括骨骼肌组织，证实了造血起源以外的其他谱系。这一观察结果暗示了以下两种可能性：1）多能干细胞的存在。2）骨髓干细胞的可塑性。另外，两种不同特性的细胞的融合被认为是这种转分化的原因。在转分化为骨骼肌的情况下，这三种可能性中的主要贡献机制尚不清楚。本课题旨在研究GFP转基因小鼠骨髓细胞移植后，骨髓细胞向骨骼肌组织转分化的机制。照射正常成年小鼠或具有c-kit突变的W/W小鼠。此外，在体外系统中，我们打算建立具有向骨骼肌分化潜能的细胞系。首先，移植GFP标记的KSL细胞后，我们可以很容易地检测到γ GFP表达的骨骼肌。这种GFP表达逐渐减少，并在30天后消失。然而，来自该移植小鼠的单个肌纤维的培养显示了GFP表达的表达，表明从移植的KSL细胞转化为具有干细胞特征的卫星面纱。另一方面，我们现在正在研究具有分化成骨骼肌组织潜力的细胞系。

Recently, the differentiation. into other lineages than hematopoietic origein was confirmed after bone marrow transplantation not only in mice but also in humans, including skeletal muscle tissue. This observation imply the following two possibilities; 1) the presence of pluripotent stem cells. in bone marrow, 2) the plasticity of bone marrow stem cells. Otherwise, the fusion of two kinds of cells with different characteristics was proposed to be the cause of this transdifferentiation. In the case of the transdifferentiation into skeletal muscle, the major contribution mechanism among these three possibilities is obscure. In this project, -we intended to analyze the mechanism four the transdifferentiation of bone, marrow cells into skeletal muscle tissue after the transplantation of bone marrow cells from GFP transgenic mice. into irradiated normal adult mice or W/W mice with c-kit mutation. In addition, in vitro system, we intended to establish, the cell line with the differentiation potential into skeletal muscle. First, after transplanting the KSL cells with GFP labeling, we could easily detect the skeletal muscle with y GFP expression. This GFP expression decreased gradually and faded out after 30 days. However, the culture of single muscle fiber from this transplanted mice revealed the expression with GFP expression, indicating the conversion into satellite veils with stem cell characteristics from transplanted KSL cells. On the other hand, we are now in the way to characterize the cell line with differentiation potential into skeletal muscle tissue.