Exosome therapy for acute stroke with large artery occlusion

摘要： 大的脑血管闭塞是缺血性中风中最致残和危及生命的形式。 人类中风主要发生在中年晚期及以后。大约三分之二的合格患者 用tPA治疗的患者经历不完全再灌注。血栓切除术现在也是一种标准的护理， 治疗大血管闭塞的急性中风。然而，闭塞大血管的再通 血栓切除术仅导致约71%的患者获得改善的组织再灌注，通常是不完全的。在 此外，由于不利的大缺血核心，许多患有大动脉闭塞的患者不适合于 接受tPA或血栓切除术。缺血组织再灌注的患者与 良好的临床效果。因此，迫切需要开发与tPA组合的疗法， 血栓切除术以增强脑灌注，从而增强tPA的治疗效果， 血栓切除术单一疗法。此外，阻断缺血性核心扩张的疗法将增加缺血性心脏病患者的数量。 有资格接受tPA和血栓切除术的患者。采用大鼠大脑中动脉栓塞模型 动脉闭塞（eMCAO）和短暂性MCAO（tMCAO，缺血/再灌注），我们发现外泌体 在eMCAO或CEC-exos之后与tPA组合的来自脑内皮细胞（CEC-exos）的 在tMCAO后再灌注时给药显著增加了再通和下游脑血流量。 与单独的tPA或tMCAO相比，血脑屏障（BBB）渗漏和梗死减少。 外来体是含有脂质、蛋白质和RNA（包括微小RNA（miR））的纳米囊泡。我们 初步数据表明，外泌体货物miR可能有助于CEC-exos在结肠癌中的治疗作用。 与tPA联合治疗急性中风，作用于脑内皮细胞，抑制 促进血栓形成和BBB破坏。因此，我们建议开发CEC-exo疗法作为一种治疗方法， 加强急性缺血性卒中的tPA和血栓切除术治疗。目标1：调查 CEC-exo疗法作为一种连续性治疗是否增强了tPA和血栓切除术治疗， 老年大鼠大动脉闭塞后。目的2是研究CEC外泌体货物miR是否 有助于CEC-exos-放大的血栓溶解，从而减少神经血管损伤。目标3 研究了一组特殊的CEC-exo货物miR是否有助于CEC-exos对肿瘤的治疗作用。 通过抑制血脑屏障前体渗漏和血栓形成基因的网络而引起的中风引起的神经血管损伤。 实现这些目标将可能导致基于机制的外泌体的发展 作为增强急性缺血性卒中的tPA和血栓切除术治疗的连续性治疗， 从而改善神经学结果。

Abstract: Large cerebral vessel occlusion is the most disabling and life-threatening form of ischemic stroke. Human stroke primarily occurs in late middle age and beyond. Approximately two thirds eligible patients treated with tPA experience incomplete reperfusion. Thrombectomy is now also a standard of care for treatment of acute stroke with large vessel occlusion. However, recanalization of the occluded large vessels by thrombectomy only leads to ~71% of patients achieving improved tissue reperfusion, often incomplete. In addition, due to unfavorably large ischemic cores, many patients with large artery occlusion are not eligible to receive tPA or thrombectomy. Patients with reperfusion of the ischemic tissue are closely associated with good clinical outcome. Thus, there is a compelling need to develop therapies in combination with tPA and thrombectomy to enhance cerebral perfusion and thereby augment the therapeutic efficacy of tPA and thrombectomy monotherapies. Also, therapies to block ischemic core expansion will increase numbers of patients who would be eligible to receive tPA and thrombectomy. Using rat models of embolic middle cerebral artery occlusion (eMCAO) and transient MCAO (tMCAO, ischemia/reperfusion), we found that exosomes derived from cerebral endothelial cells (CEC- exos) in combination with tPA after eMCAO or CEC-exos given upon reperfusion after tMCAO substantially increased recanalization and downstream cerebral blood flow (CBF), and reduced blood brain barrier (BBB) leakage and infarction compared to tPA or tMCAO alone. Exosomes are nano-vesicles that contain lipids, proteins, and RNAs including microRNAs (miRs). Our preliminary data suggest that exosomal cargo miRs likely contribute to the therapeutic effect of CEC-exos in combination with tPA on acute stroke by acting on cerebral endothelial cells to suppress proteins that promote thrombosis and BBB disruption. We thus propose to develop CEC-exo therapy as an adjunctive treatment to enhance tPA and thrombectomy treatments of acute ischemic stroke. Aim 1 is to investigate whether the CEC-exo therapy as an adjunctive treatment enhances tPA and thrombectomy treatments in aged rats after large artery occlusion. Aim 2 is to investigate whether CEC exosomal cargo miRs contribute to CEC-exos-amplified thrombolysis leading to reduction of neurovascular damage. Aim 3 investigates whether a special set of CEC-exo cargo miRs contribute to the therapeutic effect CEC-exos on stroke- induced neurovascular damage by suppressing a network of pro-BBB leakage and thrombotic genes. Accomplishing these aims will potentially lead to development of a mechanistically based exosome therapy as an adjunctive treatment to enhance tPA and thrombectomy treatments of acute ischemic stroke, leading to improvement in the neurological outcome.