Centro Nacional de Microbiologia, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain.
School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland, United Kingdom.
Int J Parasitol. 2020 Aug;50(9):635-645. doi: 10.1016/j.ijpara.2020.04.010. Epub 2020 Jul 8.
Helminth parasites have a remarkable ability to persist within their mammalian hosts, which is largely due to their secretion of molecules with immunomodulatory properties. Although the soluble components of helminth secretions have been extensively studied, the discovery that helminths release extracellular vesicles (EVs) has added further complexity to the host-parasite interaction. Whilst several studies have begun to characterise the molecules carried by helminth EVs, work aimed at investigating their biological functions has been hindered by a lack of helminth-specific EV markers. To begin to address this, we summarised helminth EV literature to date. With a focus on the protein and microRNA (miRNA) cargo, we aimed to detect similarities and differences across those major groups of helminths for which data are available; namely nematodes, trematodes and cestodes. Pfam analysis revealed that although there is no universal EV marker for all helminth species, the EF-hand protein family was present in all EV datasets from cestodes and trematodes, and could serve as a platyhelminth EV biomarker. In contrast, M13 metallopeptidases and actin may have potential as markers for nematode EVs. As with proteins, many miRNA families appeared to be species-, stage-, or dataset-specific. Two miRNA families were common to nematode EVs (mir-10 and let-7); the miRNA cargo of EVs secreted by clade I species appeared somewhat different from species from other clades. Five miRNA families (mir-71, mir-10, mir-190, let-7 and mir-2) were shared by all trematode species examined. Our analysis has identified novel markers that may be used in studies aimed at characterising helminth EVs and interrogating their function at the host-parasite interface. In addition, we discuss the heterogeneity of methods used for helminth EV isolation and emphasise the need for a standardised approach in reporting on helminth EV data.
寄生虫具有在哺乳动物宿主体内长期存在的显著能力，这主要归因于它们分泌具有免疫调节特性的分子。尽管寄生虫分泌物的可溶性成分已经得到了广泛的研究，但寄生虫释放细胞外囊泡（EVs）的发现为宿主-寄生虫相互作用增添了更多的复杂性。虽然已经有几项研究开始描述寄生虫 EV 携带的分子，但由于缺乏寄生虫特异性 EV 标记物，针对其生物学功能的研究工作受到了阻碍。为了解决这个问题，我们总结了迄今为止寄生虫 EV 的文献。我们重点关注蛋白质和 microRNA（miRNA）货物，旨在检测那些有数据可用的主要寄生虫群体（即线虫、吸虫和绦虫）之间的相似性和差异性。Pfam 分析表明，虽然没有针对所有寄生虫物种的通用 EV 标记物，但 EF 手蛋白家族存在于所有来自绦虫和吸虫的 EV 数据集，并且可以作为扁形动物 EV 的生物标志物。相比之下，M13 金属肽酶和肌动蛋白可能有作为线虫 EV 标志物的潜力。与蛋白质一样，许多 miRNA 家族似乎是物种特异性、阶段特异性或数据集特异性的。两个 miRNA 家族在线虫 EV 中常见（mir-10 和 let-7）；I 类物种分泌的 EV 的 miRNA 货物似乎与其他类群的物种有些不同。五个 miRNA 家族（mir-71、mir-10、mir-190、let-7 和 mir-2）被所有检查的吸虫物种共享。我们的分析确定了可能用于描述寄生虫 EV 并研究其在宿主-寄生虫界面功能的新型标记物。此外，我们讨论了寄生虫 EV 分离方法的异质性，并强调了在寄生虫 EV 数据报告中采用标准化方法的必要性。
