Discovery for the Target Molecules to Control. Glial Scar Formation after Spinal Cord Injury

脊髓损伤是中枢神经系统中最严重的创伤之一，每年导致数千名新患者。从创新这种损伤的治疗方法的角度来看，适当地控制“胶质瘢痕”是非常重要的，因为这种瘢痕被认为会干扰轴突的再生。在损伤后可以再生的周围神经系统中，周围神经中的雪旺细胞，即髓鞘细胞，在损伤后增殖并占据损伤区域。再生轴突经过“雪旺细胞堆积区”。因此，我们重点控制少突胶质前体细胞，即中枢神经系统中的髓鞘细胞，使其占据脊髓损伤区域，帮助轴突再生。在本研究项目中，我们首先建立了小鼠少突胶质细胞的原代培养，使我们能够通过体外实验来揭示分子功能。已知的是，如果…，少突胶质细胞以未成熟形式增殖更多的培养条件包含了足够的生长因子。目前尚不清楚生长因子是否传递了保持细胞处于未成熟状态的特定效果。从蛋白质表达分析中，我们选择了众所周知的细胞周期促进分子Cyclin D1分子，因为它的蛋白水平与少突胶质细胞的未成熟状态有很强的相关性。通过克隆Cyclin D1，产生分子突变形式，基因转移到细胞，分析分化标志物，研究Cyclin D1在少突胶质细胞成熟过程中的分子功能。我们发现，Cyclin D1除了具有细胞周期调节功能外，还具有明显的调控少突胶质细胞成熟的机制。在未来的研究中，我们计划将这些发现引入到脊髓损伤的动物模型中，看看能否控制脊髓损伤后少突胶质细胞的增殖，防止胶质瘢痕的形成。我们还进行了DNA微阵列分析，以寻找与少突胶质细胞未成熟状态相关的分子。我们的小鼠少突胶质细胞的原代培养是有帮助的，我们可以鉴定出20个可能与少突胶质细胞成熟有关的基因。我们计划在未来探索每个分子的分子功能。较少

Spinal cord injury is one of the most severe trauma in central nervous systems, resulting several thousand new patients every year. From the view point of innovating new therapeutic approach for this injury, the proper control of "Glial Scar" is very important because the scar is believed to interrupt regenerating axons. In peripheral nervous systems, which can regenerate after injury, Schwann cells, myelinating cell in peripheral nerve, proliferate after injury and they occupy the damaged area. The regenerating axons go though "Schwann cell packed area". Therefore, we put focus on controlling oligodendrocyte precursor cells, myelinating cells in central nervous systems, so that they occupy the damaged area in spinal cord and help regenerating axons.In this research project, we first worked on the establishment of primary culture of mouse oligodendrocyte, which enable us to reveal molecular function by in vitro experiments. Oligodendrocytes are known to proliferate in immature form if … More the culture condition contain enough growth factors. It is not known whether growth factors convey any specific effect to keep the cells in immature status. From the protein expression analysis, we chose Cyclin D1 molecule, well known cell cycle promoting molecule, because its protein level shows strong correlation with immature status of oligodendrocyte. Molecular function of Cyclin D1 on oligodendrocyte maturation is investigated by cloning Cyclin D1, generating mutant forms of the molecule, gene transfer to the cells and analyzing differentiation markers. We found that Cyclin D1 has distinct mechanism to control oligodendrocyte maturation apart from its cell-cycle regulating function. For the future studies, we are planning to introduce these finding to animal model of spinal cord injury to see whether we can control proliferating oligodendrocyte in after spinal cord injury and prevent glial scar formation.We also perform DNA microarray analysis to survey the molecules which is relevant to immature status of oligodendrocyte. Our primary culture of mouse oligodendrocyte is helpful and we could identified 20 genes which is possibly related to oligodendrocyte maturation. We are planning to explore molecular function of each molecules in the future. Less