ES CELL TRANSPLANTATION AFTER SPINAL CORD INJURY

赠款资金被要求支持一个新的研究计划项目，旨在开始探索胚胎干细胞移植恢复脊髓损伤后失去的功能的潜力。拟议项目小组的成员已经开发了与小鼠ES细胞分化神经谱系，减少神经系统细胞死亡的方法和创伤性脊髓损伤的啮齿动物模型的工作经验。在形成本提案特定背景的实验中，项目团队成员获得了小鼠ES细胞衍生的神经谱系细胞（ESNLC）可以成功移植到大鼠脊髓撞击损伤后9天形成的空洞/囊肿中的证据。这些移植的ESNLC存活至少数周，部分填充空洞并迁移到宿主组织中，并表达分化的少突胶质细胞，星形胶质细胞和神经元的标记物。所要求的计划项目资金将使项目团队成员能够以系统和假设驱动的方式建立这些早期实验。基于直接观察到大多数移植的ESNLC在移植后的前48小时内死亡，特别是神经元在随后的几天内继续死亡，这里提出的实验的重点将是通过旨在阻断细胞凋亡和兴奋性毒性的药理学和遗传工程方法来改善移植的ESNLC的存活。预计在随后几年中进行的工作可能会以其他方式优化ESNLC移植程序。

Grant funds are requested to support a new research Program Project aimed at initiating an exploration of the potential of embryonic stem (ES) cell transplantation for restoring lost functions after spinal cord injury. Members of the proposed Project team have already developed experience working with mouse ES cells differentiated down neural lineages, methods for reducing cell death in the nervous system, and rodent models of traumatic spinal cord injury. In the experiments that form the specific background for the present proposal, Project team members have obtained evidence that mouse ES-cell derived neural lineage cells (ESNLCs) can be successfully transplanted into the syrinx/cyst that forms nine days after impact injury to the rat spinal cord . These transplanted ESNLCs survived for at least many weeks, partially filling the syrinx and migrating into host tissue, and expressed markers for differentiated oligodendrocytes, astrocytes, and neurons. The requested Program Project funding would enable Project team members to build on these early experiments in a systematic and hypothesis-driven fashion. Based on direct observations that a majority of transplanted ESNLCs die over the first 48 hours following transplantation and that neurons in particular continue to die over subsequent days, the emphasis of the experiments proposed here will be on improving the survival of transplanted ESNLCs through pharmacological and genetic engineering approaches aimed at blocking apoptosis and excitotoxicity. It is anticipated that work performed in subsequent years may be directed at optimizing the ESNLC transplantation procedure in other ways.