Exosome therapy for acute stroke with large artery occlusion

摘要： 大血管闭塞是最具致残性和生命威胁的缺血性卒中。 人类中风主要发生在中年后期及以后。约三分之二符合条件的患者 TPA治疗后再通不全。血栓切除术现在也是一项标准的护理 急性卒中大血管闭塞的治疗。然而，闭塞的大血管的再通 通过血栓切除只会导致~71%的患者获得改善的组织再通，往往是不完全的。在……里面 此外，由于不利的大的缺血核心，许多大动脉闭塞的患者没有资格 接受tPA或血栓切除术。缺血组织再灌流的患者与 临床效果良好。因此，迫切需要开发与tPA和tPA相结合的疗法。 血栓消融术增强脑血流灌注从而增强tPA和TPA的疗效 血栓消融术单一疗法。此外，阻断缺血核心扩张的治疗将增加 有资格接受组织型纤溶酶原激活剂和血栓切除术的患者。大鼠大脑中动脉栓塞术模型的建立 动脉闭塞(EMCAO)和短暂性MCAO(tMCAO，缺血/再灌注)，我们发现外切体 脑内皮细胞来源(CEC-exos)与tPA联合应用 在tMCAO后再灌注时给予显著增加再通和下游脑血流量 与单独使用tPA或tMCAO相比，TPA或tMCAO可减少脑血流(CBF)，减少血脑屏障(BBB)渗漏和脑梗塞。 Exosome是含有脂质、蛋白质和包括microRNAs(MiRs)在内的RNA的纳米囊泡。我们的 初步数据提示，胞外体MIR可能与CEC-exos的治疗作用有关。 联合tPA治疗急性卒中作用于脑内皮细胞抑制蛋白 促进血栓形成和血脑屏障破坏。因此，我们建议发展CEC-exo疗法作为一种辅助疗法。 急性缺血性卒中的凝血酶原激活剂强化治疗和血栓清除治疗。目标1是调查 CEC-exo治疗作为辅助治疗是否能提高tPA和血栓清除术的治疗效果 大鼠大动脉闭塞后衰老模型。目标2是调查CEC外体货物MIR 有助于CEC-exos扩增的溶栓，从而减少神经血管损伤。目标3 调查一组特殊的CEC-exo货物MIR是否有助于CEC-exos对 中风通过抑制血脑屏障原渗漏和血栓形成基因网络而导致神经血管损伤。 实现这些目标将有可能导致基于机械的外切体的发展 作为提高组织型纤溶酶原激活剂的辅助治疗和急性缺血性卒中的血栓清除治疗， 导致神经结果的改善。

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.