Department of Orthopaedics, UHealth Sports Medicine Institute, University of Miami Miller School of Medicine, Miami, FL 33146, USA.
Diabetes Research Institute & Cell Transplant Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
Cells. 2023 Jul 11;12(14):1824. doi: 10.3390/cells12141824.
The onset and progression of human inflammatory joint diseases are strongly associated with the activation of resident synovium/infrapatellar fat pad (IFP) pro-inflammatory and pain-transmitting signaling. We recently reported that intra-articularly injected IFP-derived mesenchymal stem/stromal cells (IFP-MSC) acquire a potent immunomodulatory phenotype and actively degrade substance P (SP) via neutral endopeptidase CD10 (neprilysin). Our hypothesis is that IFP-MSC robust immunomodulatory therapeutic effects are largely exerted via their CD10-bound small extracellular vesicles (IFP-MSC sEVs) by attenuating synoviocyte pro-inflammatory activation and articular cartilage degradation. Herein, IFP-MSC sEVs were isolated from CD10High- and CD10Low-expressing IFP-MSC cultures and their sEV miRNA cargo was assessed using multiplex methods. Functionally, we interrogated the effect of CD10High and CD10Low sEVs on stimulated by inflammatory/fibrotic cues synoviocyte monocultures and cocultures with IFP-MSC-derived chondropellets. Finally, CD10High sEVs were tested in vivo for their therapeutic capacity in an animal model of acute synovitis/fat pad fibrosis. Our results showed that CD10High and CD10Low sEVs possess distinct miRNA profiles. Reactome analysis of miRNAs highly present in sEVs showed their involvement in the regulation of six gene groups, particularly those involving the immune system. Stimulated synoviocytes exposed to IFP-MSC sEVs demonstrated significantly reduced proliferation and altered inflammation-related molecular profiles compared to control stimulated synoviocytes. Importantly, CD10High sEV treatment of stimulated chondropellets/synoviocyte cocultures indicated significant chondroprotective effects. Therapeutically, CD10High sEV treatment resulted in robust chondroprotective effects by retaining articular cartilage structure/composition and PRG4 (lubricin)-expressing cartilage cells in the animal model of acute synovitis/IFP fibrosis. Our study suggests that CD10High sEVs possess immunomodulatory miRNA attributes with strong chondroprotective/anabolic effects for articular cartilage in vivo. The results could serve as a foundation for sEV-based therapeutics for the resolution of detrimental aspects of immune-mediated inflammatory joint changes associated with conditions such as osteoarthritis (OA).
人类炎症性关节疾病的发病和进展与驻留的滑膜/髌下脂肪垫（IFP）促炎和传递疼痛信号的激活密切相关。我们最近报道称，关节内注射 IFP 来源的间充质干细胞（IFP-MSC）获得了强大的免疫调节表型，并通过中性内肽酶 CD10（脑啡肽酶）积极降解 P 物质（SP）。我们的假设是，IFP-MSC 通过其与 CD10 结合的小细胞外囊泡（IFP-MSC sEV）发挥强大的免疫调节治疗作用，从而减弱滑膜细胞的促炎激活和关节软骨降解。在此，从 CD10High 和 CD10Low 表达的 IFP-MSC 培养物中分离 IFP-MSC sEV，并使用多重方法评估其 sEV miRNA 载物。从功能上，我们研究了炎性/纤维化刺激下刺激的滑膜细胞单核培养物和 IFP-MSC 来源的软骨小球共培养物中 CD10High 和 CD10Low sEV 的作用。最后，在急性滑膜炎/脂肪垫纤维化动物模型中测试了 CD10High sEV 的治疗能力。我们的结果表明，CD10High 和 CD10Low sEV 具有不同的 miRNA 谱。sEV 中高度存在的 miRNA 的反应组分析表明它们参与了六个基因群的调节，特别是那些涉及免疫系统的基因群。与对照刺激的滑膜细胞相比，暴露于 IFP-MSC sEV 的刺激的滑膜细胞表现出明显降低的增殖和改变的与炎症相关的分子谱。重要的是，CD10High sEV 处理刺激的软骨小球/滑膜细胞共培养物表明具有显著的软骨保护作用。在治疗方面，CD10High sEV 治疗在急性滑膜炎/IFP 纤维化动物模型中通过保留关节软骨结构/组成和 PRG4（润滑素）表达的软骨细胞产生了强大的软骨保护作用。我们的研究表明，CD10High sEV 具有免疫调节 miRNA 属性，对体内关节软骨具有强烈的软骨保护/合成代谢作用。这些结果可以为基于 sEV 的治疗提供基础，以解决与骨关节炎（OA）等疾病相关的免疫介导的炎症性关节变化的有害方面。
