Group 2 innate lymphoid cells (ILC2s) are recently reported to play a more critical role in allergic diseases. We previously identified that mesenchymal stromal cells (MSCs) elicited therapeutic effects on allergic airway inflammation. Small extracellular vesicles (sEV) derived from MSCs possess striking advantages including low immunogenicity and high biosafety, and is extremely promising cell-free therapeutic agents. However, the effects of MSC-sEV on ILC2s are still unclear. Additionally, scalable isolation protocols are required for the mass production of homogenous MSC-sEV especially in clinical application. We previously reported that induced pluripotent stem cells-derived MSCs were the ideal cellular source for the large preparation of MSC-sEV. Here we developed a standardized scalable protocol of anion-exchange chromatography for isolation of MSC-sEV, and investigated the effects of MSC-sEV on ILC2 function from patients with allergic rhinitis and in a mouse ILC2-dominant asthma model. The characterization of MSC-sEV was successfully demonstrated in terms of size, morphology and specific markers. Using flow cytometry and human Cytokine Antibody Array, MSC-sEV but not fibroblasts-sEV (Fb-sEV) were found to significantly inhibit the function of human ILC2s. Similarly, systemic administration of MSC-sEV but not Fb-sEV exhibited an inhibition of ILC2 levels, inflammatory cell infiltration and mucus production in the lung, a reduction in levels of T helper 2 cytokines, and alleviation of airway hyperresponsiveness in a mouse model of asthma. Using RNA sequencing, miR-146a-5p was selected as the candidate to mediate the above effects of MSC-sEV. We next revealed the uptake of ILC2s to MSC-sEV, and that transfer of miR-146a-5p in MSC-sEV to ILC2s in part contributed to the effects of MSC-sEV on ILC2s in vitro and in a mouse model. In conclusion, we demonstrated that MSC-sEV were able to prevent ILC2-dominant allergic airway inflammation at least partially through miR-146a-5p, suggesting that MSC-sEV could be a novel cell-free strategy for the treatment of allergic diseases.

中文翻译：

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源自人间质基质细胞的小细胞外囊泡可通过递送miR-146a-5p来预防2组先天性淋巴样细胞为主的过敏性气道炎症。

据报道，第2组先天性淋巴样细胞（ILC2s）在过敏性疾病中起着更为关键的作用。我们先前发现间充质基质细胞（MSCs）对过敏性气道炎症引起治疗作用。源自MSC的小细胞外囊泡（sEV）具有显着的优势，包括低免疫原性和高生物安全性，是极有前途的无细胞治疗剂。但是，尚不清楚MSC-sEV对ILC2的影响。另外，大规模生产同质MSC-sEV需要可扩展的隔离协议，尤其是在临床应用中。我们以前曾报道过，诱导多能干细胞衍生的MSC是大规模制备MSC-sEV的理想细胞来源。在这里，我们开发了用于交换MSC-sEV的阴离子交换色谱的标准化可扩展方案，并研究了变应性鼻炎患者和小鼠ILC2型哮喘模型中MSC-sEV对ILC2功能的影响。MSC-sEV的表征已成功证明其大小，形态和特异性标记。使用流式细胞仪和人类细胞因子抗体阵列，发现MSC-sEV而非成纤维细胞-sEV（Fb-sEV）显着抑制了人ILC2的功能。同样，全身性施用MSC-sEV而非Fb-sEV表现出对ILC2水平的抑制，肺部炎症细胞浸润和粘液产生，T辅助2细胞因子水平的降低以及在小鼠模型中气道高反应性的减轻。哮喘。使用RNA测序 选择miR-146a-5p作为介导MSC-sEV的上述作用的候选药物。接下来，我们揭示了MSC-sEV对ILC2的吸收，以及MSC-sEV中miR-146a-5p向ILC2s的转移在一定程度上促进了MSC-sEV在体外和小鼠模型中对ILC2的作用。总之，我们证明了MSC-sEV能够至少部分地通过miR-146a-5p预防ILC2占主导地位的过敏性气道炎症，这表明MSC-sEV可能是一种新型的无细胞治疗过敏性疾病的策略。