Extracellular vesicles derived from amniotic fluid stem cells normalize glomerular function during progressive kidney disease.

在大多数慢性肾脏疾病（CKD）的进展过程中，足细胞和肾小球内皮细胞（GEC） 都受到了不可逆的破坏这些细胞的损伤或肾小球基底组成的变化 肾小球滤过屏障（GFB）的结构和功能改变。再- 通过刺激内源性修复机制建立GFB功能可以减缓肾脏疾病 进展 本提案中的数据显示，来自人羊水干细胞的细胞外囊泡 （hAFSC-EV）在我们的CKD、Alport综合征（AS）的动物模型中是体内肾保护性的。没有副作用或 发生免疫应答的刺激。这些EV可以激活肾小球细胞的修复机制， 货物转运。具体而言，它们调节足细胞和GEC中miR-93的水平。miR-93是一个关键 在CKD中的作用，因为其表达水平的变化与肾损伤的发展相关， 具体地，miR-93表达在小鼠和人AS肾小球和尿液样品中降低， hEV可以使miR-93水平恢复正常。我们假设hEV可以重建肾小球功能， 通过防止进一步的肾小球损伤，从而最小化肾病进展。利用转基因 Alport小鼠、人源性EV和人AS活检结合创新的空间转录组学 方法，我们将研究EV的作用机制，特别关注EV/miR-93轴的能力， “重新编程”调节肾小球细胞生物学的细胞信号网络。我们的目标还包括评估 hEV在不同AS阶段的疾病改善能力（目的1）。最后，我们的目标是研究 疾病进展期间肾小球内信号通路的变化，特别关注GEC， 在人类AS活检中验证这些数据（目的2）。 成功完成这一提案将提供新的见解的关键因素的关键维护 肾小球结构和功能。重要的是，这些知识可能适用于其他形式的CKD 并可能有助于发现新的治疗药物，专门用于减少肾小球疾病。 损害

During the progression of most chronic kidney diseases (CKD) podocytes and glomerular endothelial cells (GEC) are irreversibly damaged. Injury to these cells or changes within the composition of the glomerular basement membrane lead to alterations of the structure and function of the glomerular filtration barrier (GFB). Re- establishing GFB function by stimulating endogenous repair mechanisms could slow kidney disease progression. Data presented in this proposal show that extracellular vesicles derived from human amniotic fluid stem cells (hAFSC-EVs) are renoprotective in vivo in our animal model of CKD, Alport Syndrome (AS). No side effects or stimulation of an immune response occurred. These EVs can activate repair mechanisms in glomerular cells by cargo transfer. Specifically, they modulate the levels of miR-93 in both podocytes and GEC. miR-93 plays a key role in CKD since changes in its expression level are associated with the development of renal damage and fibrosis; specifically, miR-93 expression is decreased in mouse and human AS glomeruli and urine samples and hEVs can restore miR-93 levels to normal. We hypothesize that hEVs can re-establish glomerular function by preventing further glomerular injury, thus minimizing renal disease progression. Using transgenic Alport mice, EVs of human origin, and human AS biopsies combined with an innovative spatial transcriptomics approach, we will study the EV mechanism of action with specific focus on the ability of the EV/miR-93 axis to “re-program” cellular signaling networks that regulate glomerular cell biology. We also aim to evaluate the disease modifying capability of hEVs at different AS stages (Aim 1). Finally, we aim to study the molecular signaling pathway changes within the glomerulus during disease progression with specific focus on GEC and to validate these data in human AS biopsies (Aim 2). Successful completion of this proposal will provide novel insights into the key factors critical for maintenance of glomerular structure and function. Importantly, this knowledge would likely be applicable to other forms of CKD and possibly will facilitate the discovery of new therapeutic agents tailored specifically to minimize glomerular damage.