Extracellular Vesicles Enhance the Remodeling of Cell-Free Silk Vascular Scaffolds in Rat Aortae
Extracellular Vesicles Enhance the Remodeling of Cell-Free Silk Vascular Scaffolds in Rat Aortae
复制标题
DOI：
10.1021/acsami.0c06609
复制
发表时间：
2020-06-17
影响因子：
9.5
通讯作者：
Vorp, David A.
中科院分区：
文献类型：
--
作者：
Cunnane, Eoghan M.;Lorentz, Katherine L.;Vorp, David A.
血管组织工程的目的是开发再生血管移植物，通过旁路或用管状可生物降解支架替代有缺陷的动脉段来恢复组织功能。支架通常与干细胞或祖细胞组合以防止急性血栓形成并启动支架重塑。然而，基于细胞的技术在安全性和临床转化方面存在局限性。细胞外囊泡（EV）是由大多数细胞类型（包括干细胞和祖细胞）释放的纳米级颗粒，用于将蛋白质和RNA货物传输到全身的靶细胞。EV已被证明可以复制其亲本细胞的治疗效果;因此，来源于干细胞或祖细胞的EV可以作为血管支架的更可翻译的、无细胞的治疗基础。我们的研究旨在确定EV掺入是否对体内移植物通畅性和重塑产生积极影响。我们首先使用体外生物测定评估了人脂肪源性间充质干细胞（hADMSC）EV对血管细胞的影响。然后，我们通过将EV真空接种到多孔的基于丝的管状支架中来开发EV功能化的血管移植物。将这些构建体作为主动脉间置移植物植入刘易斯大鼠中，并将其重塑能力与hADMSC接种和空白（未接种）对照观察到的重塑能力进行比较。在体内8周后，EV组显示出与hADMSC（56%）和空白对照（82%）相比改善的通畅性（100%）。与空白组相比，EV组还产生了显著更多的弹性蛋白（126.46%）和胶原蛋白（44.59%），而与空白组相比，hADMSC组未能产生显著更多的弹性蛋白（57.64%）或胶原蛋白（11.21%）。与对照组相比，EV组中，经染色的新组织的定性染色显示内皮形成改善，平滑肌细胞浸润增加，巨噬细胞数量减少，这有助于解释该组的有利临床前结果。
Vascular tissue engineering is aimed at developing regenerative vascular grafts to restore tissue function by bypassing or replacing defective arterial segments with tubular biodegradable scaffolds. Scaffolds are often combined with stem or progenitor cells to prevent acute thrombosis and initiate scaffold remodeling. However, there are limitations to cell-based technologies regarding safety and clinical translation. Extracellular vesicles (EVs) are nanosized particles released by most cell types, including stem and progenitor cells, that serve to transmit protein and RNA cargo to target cells throughout the body. EVs have been shown to replicate the therapeutic effect of their parent cells; therefore, EVs derived from stem or progenitor cells may serve as a more translatable, cell-free, therapeutic base for vascular scaffolds. Our study aims to determine if EV incorporation provides a positive effect on graft patency and remodeling in vivo. We first assessed the effect of human adipose-derived mesenchymal stem cell (hADMSC) EVs on vascular cells using in vitro bioassays. We then developed an EV-functionalized vascular graft by vacuum-seeding EVs into porous silk-based tubular scaffolds. These constructs were implanted as aortic interposition grafts in Lewis rats, and their remodeling capacity was compared to that observed for hADMSC-seeded and blank (non-seeded) controls. The EV group demonstrated improved patency (100%) compared to the hADMSC (56%) and blank controls (82%) following eight weeks in vivo. The EV group also produced significantly more elastin (126.46%) and collagen (44.59%) compared to the blank group, while the hADMSC group failed to produce significantly more elastin (57.64%) or collagen (11.21%) compared to the blank group. Qualitative staining of the explanted neo-tissue revealed improved endothelium formation, increased smooth muscle cell infiltration, and reduced macrophage numbers in the EV group compared to the controls, which aids in explaining this group's favorable pre-clinical outcomes.