Multimodal approach investigating the immunomodulatory effect ofneural stem cells in stroke recovery

人类神经干细胞（hNSC）治疗中风显示出希望，因为它从 进行早期临床试验，以治疗中风导致的长期残疾。这 为数百万患有慢性中风的美国人带来了希望。 然而，关于注射到大脑中的干细胞是如何驱动中风的， 复苏干细胞作用机制的一个线索是最近发现的积极的 卒中恢复与脑MRI信号- T2-FLAIR信号-的相关性 接受干细胞治疗的患者我们已经成功地复制了这种干细胞诱导的FLAIR 信号，并表明其与炎症有关。这导致了我们的 中心假设：干细胞移植通过诱导再生的 炎症反应。这项资助的目的是使用大鼠皮层下卒中模型， 探讨脑卒中慢性期移植hNSC的免疫调节作用， 在区域、细胞和分子水平上使用多模式方法。在Aim 1中，我们使用MRI 和PET成像，以确定hNSC后哪些大脑区域显示炎症变化 移植，以及哪些炎症区域与恢复最相关。这也将考验 这些临床相关的成像模式作为中风恢复的生物标志物的效用。在 目的2我们使用多种工具鉴定hNSC治疗诱导的免疫变化， 表征存在的免疫细胞的类型和分子特征，以及它们的空间分布， 交互.在目的3中，我们确定哪些hNSCs分泌因子调节免疫 通过在体外和体内测试几种候选物，使用CRISPR工具调节 关键候选因素的表达。我们将研究操纵这些水平的影响， 蛋白质对中风恢复和免疫调节的作用。研究完成后，我们将 在理解hNSCs诱导的免疫调节如何影响 大脑修复这一贡献是重要的，因为它将：a）鉴定潜在的生物标志物， 治疗前和治疗后，用于hNSC诱导的恢复; B）开始描绘分子 参与脑修复的途径;以及c）最终导致识别用于治疗脑损伤的新疗法。 中风

Human neural stem cell (hNSC) therapy for stroke is showing promise as it moves from the bench into early clinical trials to treat the long term disabilities resulting from stroke. This provides hope for the millions of Americans living with the chronic, debilitating effects of stroke. Major questions remain, however, about how stem cells injected into the brain drive stroke recovery. A clue to stem cell mechanism of action is the recent discovery of the positive correlation between stroke recovery and a brain MRI signal – T2-FLAIR signal– in stroke patients treated with stem cells. We have successfully reproduced this stem cell-induced FLAIR signal in stroke-injured rats, and shown that its associated with inflammation. This led to our central hypothesis: stem cell transplantation drives recovery by inducing a regenerative inflammatory response. The objective of this grant is to use a rat model of subcortical stroke to investigate the immunomodulatory effects of hNSC transplanted at the chronic stage of stroke, at the regional, cellular and molecular levels using a multimodal approach. In Aim1 we use MRI and PET imaging to identify which brain regions show inflammatory changes after hNSC transplantation, and which inflammatory regions best correlate with recovery. This will also test the utility of these clinically relevant imaging modalities as biomarkers for stroke recovery. In Aim 2 we identify the immune changes induced by hNSC treatment using multiple tools to characterize the types and molecular signatures of the immune cells present, and their spatial interactions. In Aim 3 we determine which hNSC-secreted factors modulate the immune response by testing several candidates, in vitro and in vivo, using CRISPR tools to modulate expression of key candidate factors. We will study the impact of manipulating the levels of these proteins on stroke recovery and immunomodulation. Upon conclusion of the study, we will have made significant advancements in understanding how hNSC-induced immunomodulation affects brain repair. This contribution is significant because it will: a) identify potential biomarkers, both pre- and post-treatment, for hNSC-induced recovery; b) begin to delineate the molecular pathways involved in brain repair; and c) ultimately lead to identification of novel therapies for stroke.