Department of Neurology, University Medical Center Goettingen, Robert-Koch-Str. 40, 37075, Goettingen, Germany.
Institute of Pathology, University Medical Center Goettingen, Goettingen, Germany.
Transl Stroke Res. 2021 Feb;12(1):185-203. doi: 10.1007/s12975-020-00814-z. Epub 2020 May 2.
Stem cells such as mesenchymal stem cells (MSCs) enhance neurological recovery in preclinical stroke models by secreting extracellular vesicles (EVs). Since previous reports have focused on the application of MSC-EVs only, the role of the most suitable host cell for EV enrichment and preclinical stroke treatment remains elusive. The present study aimed to evaluate the therapeutic potential of EVs derived from neural progenitor cells (NPCs) following experimental stroke. Using the PEG technique, EVs were enriched and characterized by electron microscopy, proteomics, rt-PCR, nanosight tracking analysis, and Western blotting. Different dosages of NPC-EVs displaying a characteristic profile in size, shape, cargo protein, and non-coding RNA contents were incubated in the presence of cerebral organoids exposed to oxygen-glucose deprivation (OGD), significantly reducing cell injury when compared with control organoids. Systemic administration of NPC-EVs in male C57BL6 mice following experimental ischemia enhanced neurological recovery and neuroregeneration for as long as 3 months. Interestingly, the therapeutic impact of such NPC-EVs was found to be not inferior to MSC-EVs. Flow cytometric analyses of blood and brain samples 7 days post-stroke demonstrated increased blood concentrations of B and T lymphocytes after NPC-EV delivery, without affecting cerebral cell counts. Likewise, a biodistribution analysis after systemic delivery of NPC-EVs revealed the majority of NPC-EVs to be found in extracranial organs such as the liver and the lung. This proof-of-concept study supports the idea of EVs being a general concept of stem cell-induced neuroprotection under stroke conditions, where EVs contribute to reverting the peripheral post-stroke immunosuppression.
间充质干细胞（MSCs）等干细胞通过分泌细胞外囊泡（EVs）来增强临床前中风模型中的神经恢复。由于之前的报告仅关注 MSC-EVs 的应用，因此对于最适合用于 EV 富集和临床前中风治疗的宿主细胞的作用仍然难以捉摸。本研究旨在评估源自神经祖细胞（NPCs）的 EV 在实验性中风后的治疗潜力。使用 PEG 技术，通过电子显微镜、蛋白质组学、rt-PCR、纳米视跟踪分析和 Western blot 对 EV 进行富集和表征。在存在暴露于氧葡萄糖剥夺（OGD）的脑类器官的情况下，孵育具有特征性大小、形状、货物蛋白和非编码 RNA 含量的 NPC-EVs，与对照类器官相比，显著降低了细胞损伤。在实验性缺血后，雄性 C57BL6 小鼠体内给予 NPC-EVs 可增强神经恢复和神经再生长达 3 个月。有趣的是，这种 NPC-EVs 的治疗效果并不逊于 MSC-EVs。中风后 7 天对血液和脑组织样本进行流式细胞术分析表明，NPC-EV 给药后 B 和 T 淋巴细胞的血液浓度增加，但不影响脑细胞计数。同样，在全身给予 NPC-EVs 后的生物分布分析表明，大多数 NPC-EVs 存在于肝和肺等颅外器官中。这项概念验证研究支持 EV 是中风条件下干细胞诱导神经保护的一般概念的观点，其中 EV 有助于逆转中风后的外周免疫抑制。
