The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
Biomed Res Int. 2020 Mar 3;2020:6094562. doi: 10.1155/2020/6094562. eCollection 2020.
Exosomes are extracellular membranous nanovesicles that mediate local and systemic cell-to-cell communication by transporting functional molecules, such as proteins, into target cells, thereby affecting the behavior of receptor cells. Exosomes originating from adipose-derived mesenchymal stem cells (ADSCs) are considered a multipotent and abundant therapeutic tool for tissue injury. To investigate ADSC-secreted exosomes and their potential function in tissue repair, we isolated exosomes from the supernatants of ADSCs via ultracentrifugation, characterized them via transmission electron microscopy, nanoparticle tracking analysis, and Western blot analysis. Then, we determined their protein profile via proteomic analysis. Results showed that extracellular vesicles, which have an average diameter of 116 nm, exhibit a cup-shaped morphology and express exosomal markers. A total of 1,185 protein groups were identified in the exosomes. Gene Ontology analysis indicated that exosomal proteins are mostly derived from cells mainly involved in protein binding. Protein annotation via the Cluster of Orthologous Groups system indicated that most proteins were involved in general function prediction, posttranslational modification, protein turnover, and chaperoning. Further, pathway analysis revealed that most of the proteins obtained participated in metabolic pathways, focal adhesion, regulation of the actin cytoskeleton, and microbial metabolism. Some tissue repair-related signaling pathways were also discovered. The identified molecules might serve as potential therapeutic targets for future studies.
外泌体是一种细胞外的膜性纳米囊泡，通过将功能性分子（如蛋白质）转运到靶细胞中，从而影响受体细胞的行为，介导局部和全身的细胞间通讯。脂肪来源的间充质干细胞（ADSCs）来源的外泌体被认为是一种多功能且丰富的组织损伤治疗工具。为了研究 ADSC 分泌的外泌体及其在组织修复中的潜在功能，我们通过超速离心从 ADSC 的上清液中分离出外泌体，通过透射电子显微镜、纳米颗粒跟踪分析和 Western blot 分析对其进行了表征。然后，我们通过蛋白质组学分析确定了它们的蛋白质图谱。结果表明，具有 116nm 平均直径的细胞外囊泡呈杯状形态，并表达外泌体标志物。在外泌体中鉴定出 1185 种蛋白质组。GO 分析表明，外泌体蛋白主要来源于参与蛋白结合的细胞。通过 COG 系统进行的蛋白质注释表明，大多数蛋白质参与一般功能预测、翻译后修饰、蛋白质周转和伴侣。进一步的通路分析表明，获得的大多数蛋白质参与代谢途径、焦点黏附、肌动蛋白细胞骨架的调节和微生物代谢。还发现了一些与组织修复相关的信号通路。鉴定出的分子可能成为未来研究的潜在治疗靶点。
