Inhalation Delivery of Exosome and microRNA Therapy for Lung Fibrosis

项目摘要 特发性肺纤维化（IPF）是一种最终致命的疾病，其唯一的治愈性治疗是肺 移植IPF的特征在于肺纤维化病变的形成，最终导致 疤痕和肺功能的逐渐丧失。尽管有一些较新的治疗方法，IPF患者仍有 一旦确诊，中位生存率仅为3-5年。显然，新的治疗方法 来治疗这种毁灭性的疾病干细胞治疗是一种很有前途的方法。在 在过去的8年里，我们的实验室一直在开发肺球状体细胞（LSC）作为一种新的治疗来源， LSC治疗IPF患者的临床试验正在寻求FDA批准。 尽管如此，基于干细胞的治疗面临着几个重要的限制。活细胞需要 在使用前仔细保存和处理，细胞移植携带一定的 免疫原性和致瘤性风险。重要的是，活的干细胞不能被输送到肺部， 通过吸入，这是将治疗剂递送到肺的最方便和有效的途径。 最近，我们和其他人发现了一个新奇而令人兴奋的现象， 发挥其有益的影响，主要是通过分泌再生因子，继续促进 内源性修复在构成本申请基础的初步研究中，我们 发现培养的LSC的分泌物与LSC一样有效，如果不是更有效的话 在疾病的啮齿动物模型中减轻和解决IPF。在寻求积极的 在LSC分泌物中的组分中，我们发现LSC分泌大量的外泌体（30-150 由许多细胞类型分泌的nm囊泡）。我们已经表明，来源于LSC的外泌体 （LSC-Exo）对受伤的肺具有治疗性和再生性，这表明这些纳米结构是 主要负责IPF啮齿动物模型中对LSC分泌物的修复反应。已知 外泌体携带微小RNA（miRs）货物，在细胞间相互作用中发挥重要作用， 通讯和组织修复，事实上，我们发现LSC-Exo高度富集miR- 30 a和Let-7。在这项拟议的研究中，我们计划确定安全性和有效性以及中等剂量 在IPF啮齿动物模型中肺修复所需的LSC-Exo的有效剂量，以确定 肺中LSC-Exo的受体细胞，并确定外泌体的相关分子靶标 介导的修复和恢复。我们假设LSC-Exo中的关键miRs，如miR-30 a和miR-30 b， Let-7是TGF-β信号通路的介质，使用scRNA-Seq产生的数据，我们 最终将确定这些外泌体中的进一步miR富集是否能够实现最佳的肺修复。 来源于干细胞的无细胞或无生命治疗剂的开发具有潜力， 彻底改变目前的再生医学实践。

PROJECT ABSTRACT Idiopathic pulmonary fibrosis (IPF) is an ultimately fatal disease whose only curative treatment is lung transplant. IPF is characterized by formation of fibrotic lesions in the lung, eventually resulting in scarring and progressive loss of lung function. Despite some newer treatments, IPF patients still have a median survival rate of only 3-5 years once diagnosed. Clearly, new therapeutic approaches are needed to treat this devastating disease. A promising avenue of approach is stem cell therapy. In the past 8 years, our lab has been developing lung spheroid cells (LSCs) as a novel source of therapeutic lung cells, and FDA approval of clinical trials with LSC treatment of patients with IPF are being pursued. Nonetheless, stem cell-based therapy faces several important limitations. Live cells need to be carefully preserved and processed before usage, and cell transplantation carries certain immunogenicity and tumorigenicity risks. Importantly, live stem cells cannot be delivered to the lung via inhalation, which is the most convenient and effective route to deliver therapeutics to the lung. Recently, we and others have made the novel and exciting observation that many adult stem cells exert their beneficial effects mainly through secretion of regenerative factors that go on to promote endogenous repair. In the preliminary studies that form the basis for this application, we have discovered that secretions from cultured LSCs are just as, if not more, effective than the LSCs themselves in attenuating and resolving IPF in rodent models of the disease. In the quest for active components in the LSC secretions, we found that LSCs secrete large numbers of exosomes (30-150 nm vesicles secreted by numerous cell types). We have shown that exosomes derived from LSCs (LSC-Exo) are therapeutic and regenerative to the injured lung, suggesting these nanostructures are largely responsible for the reparative response to LSC secretions in rodent models of IPF. It is known that exosomes carry microRNAs (miRs) cargoes that could play important roles in cell-cell communication and tissue repair, and indeed we found that LSC-Exo are highly enriched with miR- 30a and Let-7. In this proposed study, we plan to determine safety and efficacy as well as medium effective dose of LSC-Exo required for lung repair in rodent models of IPF, to determine the major recipient cells of LSC-Exo in the lung, and determine that the relevant molecular target(s) of exosomal mediated repair and recovery. We hypothesize that key miRs withing LSC-Exo such as miR-30a and Let-7 are mediators of the TGF-beta signaling pathway, using the data produced by scRNA-Seq we will finally determine whether further miR enrichment in these exosomes achieves optimal lung repair. The development of cell-free or non-living therapeutics derived from stem cells has the potential to revolutionize current regenerative medicine practice.