An Interneuron-based Cell Therapy for Epilepsy

 描述（由申请人提供）：GABA祖细胞移植到中枢神经系统中已显示出治疗神经系统疾病的巨大前景。我们的实验室证明，GABA表达的中间神经元，来自啮齿动物胚胎内侧神经节隆起（MGE），迁移，整合，并增加移植后的抑制。这些细胞的潜在治疗益处在以下动物模型中报道：癫痫、帕金森病、阿尔茨海默病、神经性疼痛、精神分裂症、焦虑和精神病。在之前的NIH支持的资助周期中，为了响应NINDS癫痫研究“基准”，我们开发了一种使用从小鼠胚胎中收获的MGE祖细胞的成人移植策略，并发表了第一项研究，证明MGE移植显着抑制自发性癫痫发作并改善认知或行为并发症在获得性癫痫动物模型中。这些发现与我们的假设一致，即通过产生新的中间神经元来增强GABA介导的抑制，从而在具有过度兴奋特征的疾病（如癫痫）中提供治疗益处。将这些发现转化为临床，最终需要更全面地了解潜在的机制。然而，MGE移植的研究还没有充分解决不同的中间神经元亚群如何影响宿主电路以及哪些亚型是观察到的治疗活性所必需的问题。为了解决这些问题，我们提出了实验来研究从内侧和尾侧神经节隆起收获的祖细胞。这些细胞将被移植到新生儿和成年海马体中，以及常见的获得性癫痫啮齿动物模型中。供体小鼠将掺入神经元间特异性Cre重组酶系，以及floxed、通道视紫红质（CHR2）、囊泡GABA转运蛋白缺陷（VGAT）和白喉毒素（DT）动物。技术将涉及使用体外维持的急性脑切片、可视化膜片钳记录结合光遗传学刺激和病毒突触示踪剂。还将应用视频脑电图监测、免疫荧光、行为和共聚焦显微镜技术。提出了两个具体目标：（i）评估移植的祖细胞在宿主脑中的整合，和（ii）鉴定移植的祖细胞的治疗益处所必需的中间神经元亚群。我们的研究结果有望推进我们的长期目标，即开发一种新的基于中间神经元的细胞疗法来治疗难治性癫痫。

 DESCRIPTION (provided by applicant): Transplantation of GABA progenitors into the central nervous system has shown great promise for the treatment of neurological disease. Our laboratories demonstrated that GABA-expressing interneurons, derived from the rodent embryonic medial ganglionic eminence (MGE), migrate, integrate, and increase inhibition following transplantation. Potential therapeutic benefits of these cells were reported in animal models of: epilepsy, Parkinson's disease, Alzheimer's disease, neuropathic pain, schizophrenia, anxiety and psychosis. During the previous NIH-supported funding cycle and in response to NINDS epilepsy research "benchmarks", we developed an adult transplantation strategy using MGE progenitors harvested from mouse embryos, and published the first studies demonstrating that MGE transplantation dramatically suppressed spontaneous seizures and improved cognitive or behavioral co-morbidities in an animal model of acquired epilepsy. These findings are consistent with our hypothesis that enhancement of GABA-mediated inhibition - through the generation of new interneurons - provides therapeutic benefit in conditions featuring excess excitation such as epilepsy. Translation of these findings to the clinic, ultimately, requires a more complete understanding of underlying mechanism(s). However, studies of MGE transplantation have not adequately addressed the question of how distinct interneuron sub-population(s) influence host circuitry and which sub-types are necessary for the therapeutic activity observed. To address these issues, we propose experiments to study progenitors harvested from the medial and caudal ganglionic eminences. These cells will be transplanted in neonatal and adult hippocampus, and in a common rodent model of acquired epilepsy. Donor mice will incorporate interneuron-specific Cre-recombinase lines, as well as floxed, channelrhodopsin (CHR2), vesicular GABA transporter deficient (VGAT), and diphtheria toxin (DT) animals. Techniques will involve use of acute brain slices maintained in vitro, visualized patch clamp recording in combination with optogenetic stimulation, and viral synaptic tracers. Video-EEG monitoring, immunofluorescence, behavior and confocal microscopy techniques will also be applied. Two specific aims are proposed: (i) to evaluate integration of transplanted progenitor cells in the host brain, and (ii) to identify interneuron sub-population(s) necessary fo the therapeutic benefits of transplanted progenitor cells. Our results promise to advance our long-term goal to develop a novel interneuron-based cell therapy for intractable epilepsies.