MSC extracellular vesicles for therapy of ARDS - development of a scalable process for production of the mitochondria enriched EV product

急性呼吸窘迫综合征是目前尚无有效药物治疗的危重症患者死亡的主要原因。间充质基质细胞（MSC）正在研究作为ARDS（包括与COVID-19相关的ARDS）的细胞疗法。临床研究一致证明了安全性，最近的一些研究证明了显著和有临床意义的疗效。细胞外囊泡是MSC分泌组的关键成分，越来越多的研究（包括我们自己的研究）表明，EV重现了MSC在ARDS临床前模型中的作用。我们已经确定线粒体转移是EV免疫调节、抗微生物、修复作用和改善肺泡毛细血管完整性的核心-因此针对ARDS发病机制的所有关键方面。EV的进一步临床开发的主要障碍是临床级EV的成本有效的大规模生产。本项目的主要目的是开发和优化使用临床级MSC和无zeno试剂在生物反应器系统中生产富集EVS的可扩展方法，这将很容易进行大规模GMP生产，同时证明治疗有用性和建立的作用机制。将在随后的DPFS应用中促进下游开发计划，重点是在小型和大型动物模型中测试所得EV产品的治疗功效，扩大EV生产方案并将其转移到c-GMP设施。该产品的最终用户是ARDS患者和ICU临床医生。目前还没有针对ARDS的有效治疗;因此，这种治疗剂旨在解决未满足的临床需求领域。虽然该项目的重点是ARDS，但数据将与其他肺部疾病（如COPD、IPF、支气管扩张症）和炎症性疾病（如脓毒症）相关，其中炎症失调和线粒体功能障碍是发病机制的重要方面。

Acute Respiratory Distress Syndrome is a major cause of mortality in the critically ill patients with no effective pharmacological treatment. Mesenchymal stromal cells (MSCs) are being investigated as a cell therapy for ARDS including that associated with COVID-19. Clinical investigations have uniformly demonstrated safety with some recent investigations demonstrating significant and clinically meaningful efficacy. Extracellular vesicles are key components of MSC secretome, and growing number of studies including our own demonstrate that EVs recapitulate effects of MSCs in the preclinical models of ARDS. We have identified mitochondrial transfer to be central for EV immunomodulatory, antimicrobial, reparative effects and improvement in the alveolar-capillary integrity- thus targeting all key aspects of ARDS pathogenesis. The main obstacle for further clinical development of EVs is cost effective large scale production of clinical grade EVs.The main objective of the present project is to develop and optimise a scalable method of production of the mitochondria-enriched EVs in the bioreactor system using clinical grade MSCs and zeno-free reagents, which will be readily amenable to large scale GMP production whilst demonstrating therapeutic usefulness and established mechanism of action.Successful transition through this objective will prompt downstream development plans in subsequent DPFS application focused on the testing of the therapeutic efficacy of the resultant EV product in the small and large animal models, scale up of the EV production protocol and its transfer to the c-GMP facility.The end users of this product are ARDS patients and the ICU clinicians. Currently there is no effective treatment for ARDS; this therapeutic agent therefore aims to address an area of unmet clinical need. While this project is focused on ARDS, the data will be relevant to other lung conditions such as COPD, IPF, broncheactasis and inflammatory conditions such as sepsis where dysregulated inflammation and mitochondrial dysfunction are important aspects of pathogenesis.