FAS Controls Exosome-Mediated miRNA Transfer in MSC-Based Therapy

项目说明 系统性硬化症/硬皮病(SSC)是一种结缔组织疾病，其特征是血管、免疫和 皮肤和内脏的纤维性改变。众所周知，SSc患者骨量减少的发生率很高， 但导致SSc患者骨质疏松的病理生理机制尚不清楚。全身输液 间充质干细胞(MSCs)在各种自身免疫性疾病中产生治疗效果；然而， 这种以骨髓间充质干细胞为基础的疗法背后的原因尚不完全清楚。作为一个分泌体，MSCs释放大量的 大量的细胞因子和小泡，用于免疫调节和与周围细胞的交流。这个 这项提议的目标是研究小囊泡是如何由一组膜运输蛋白控制的 骨髓间充质干细胞移植中的细胞成分重用。我的初步数据显示，MSCT显著 通过重建组织动态平衡和血统承诺拯救SSC小鼠的疾病表型 托管MSCs。MiRNA-151-5p被受体MSCs通过外切体转运重新利用，导致显著 恢复宿主MSCs的谱系选择。在供体间充质干细胞中组装的微泡转运复合体 外切体介导微核糖核酸转移的调控胞吐作用。此外，发育中的内皮细胞基因座-1 免疫抑制分子(Del-1)在MSCs中表达，并通过外体释放抑制中性粒细胞 迁移。这一提议的中心假设是细胞成分从供体转移到 受体MSCs通过Fas组装的胞吞作用改善自身免疫性疾病的表型 机械设备。在K99阶段，我将探索MSCT在SSC小鼠中的疗效并揭示其相互作用 免疫细胞和组织特异性干细胞之间的相互作用以阐明SSc的病理生理机制 (目标1；K99)。由于miRNA-151-5p已被确定可从供体MSCs转移到受体MSCs，我将 确定miRNA-151-5p在骨髓间充质干细胞分化中的作用及应用miRNA-151-5p基因治疗SSC 小鼠(目标2；K99)。在R00阶段，我将通过直接输液来确定外切体在MSCT中的作用 并研究胞吐作用分子Rab27a在调节细胞外排出蛋白中的作用。 外切体释放。我将从MSCs中鉴定出一种新的微泡运输复合体，并确定其功能 在控制单元组件重用方面(目标3；R00)。最后，我将检查Del-1的治疗效果， 可以通过供体MSCs的外切体释放，以抑制细胞因子的产生和疾病表型(AIM 4；R00)。在成功完成具体目标后，这项翻译研究将扩大我们对 SSC的发病机制，并描述基于MSC的治疗的详细机制。在我的主要导师 Hajishengallis博士和史博士的培训计划将为扩展和发展提供必要的机会 协作环境中的知识和技能。一支公认的优秀导师团队和 合作者将拓宽我在不同研究领域的培训。在他们的监督和指导下，这 NIH K99/R00奖将极大地提高我作为一名独立研究员开始科学生涯的能力。

Project Description Systemic sclerosis/scleroderma (SSc) is a connective tissue disease characterized by vascular, immune and fibrotic changes in the skin and internal organs. SSc patients are known to have high prevalence of osteopenia, but the pathophysiological mechanism causing this osteoporosis in SSc patients is unknown. Systemic infusion of mesenchymal stem cells (MSCs) yields a therapeutic effect in a variety of autoimmune diseases; however, the reasons behind this MSC-based therapy are not fully understood. As a secretome, MSCs release large amounts of cytokines and small vesicles for immunoregulation and communication with surrounding cells. The goal of this proposal is to investigate how small vesicles are controlled by a set of membrane traffic proteins for cell component reuse in MSC transplantation (MSCT). My preliminary data show that MSCT significantly rescues disease phenotypes in SSc mice through rebuilding tissue homeostasis and lineage commitment of host MSCs. miRNA-151-5p is reused by recipient MSCs through exosome trafficking resulting in markedly recovered lineage selection of host MSCs. A micro-vesicle trafficking complex assembled in donor MSCs regulated exocytosis for exosome-mediated miRNA transfer. In addition, developmental endothelial locus-1 (Del-1), an immune suppressive molecule, expresses in MSCs and releases via exosomes to inhibit neutrophil migration. The central hypothesis of this proposal is that cell component transferred from donor to recipient MSCs ameliorates autoimmune disease phenotypes through FAS-assembled exocytotic machinery. During the K99 phase, I will explore the efficacy of MSCT in SSc mice and uncover the interplay between immune cells and tissue-specific stem cells to elucidate the pathophysiological mechanism of SSc (Aim 1; K99). Since miRNA-151-5p has been identified to transfer from donor to recipient MSCs, I will determine the function of miRNA-151-5p in MSC differentiation and use miRNA-151-5p gene therapy in SSc mice (Aim 2; K99). During the R00 phase, I will determine the role of the exosome in MSCT by direct infusion of exosomes for disease treatment and examine the role of the exocytosis molecule Rab27a in regulation of exosome release. I will identify a novel micro-vesicle trafficking complex from MSCs and determine its function in controlling cell component reuse (Aim 3; R00). Finally, I will examine the therapeutic effect of Del-1, which can be released via exosomes from donor MSCs to restrain cytokine production and disease phenotypes (Aim 4; R00). Upon successful completion of the Specific Aims, this translational study will extend our knowledge of SSc pathogenesis and describe detailed mechanisms of MSC-based therapy. Under my primary mentorship of Drs. Hajishengallis and Shi, the training plan will provide the opportunity to extend and develop the necessary knowledge and skills within a collaborative environment. An identified outstanding mentorship team and collaborators will broaden my training in different research fields. Under their supervision and guidance, this NIH K99/R00 Award will largely improve my ability to begin my scientific career as an independent investigator.