Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada.
Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada.
Front Cell Infect Microbiol. 2024 Feb 19;14:1354636. doi: 10.3389/fcimb.2024.1354636. eCollection 2024.
Extracellular vesicles (EVs) are heterogenous cell-derived membrane-bound structures which can be subdivided into three distinct classes according to distinct morphological characteristics, cellular origins, and functions. Small EVs, or exosomes, can be produced by the protozoan parasite through the evolutionarily conserved ESCRT pathway, and act as effectors of virulence and drivers of pathogenesis within mammalian hosts. Techniques for the identification of EVs of non-mammalian origin, however, remain inaccurate in comparison to their well-characterized mammalian counterparts. Thus, we still lack reliable and specific markers for -derived exosomes, which poses a significant challenge to the field.
Herein, we utilized serial differential ultracentrifugation to separate -derived EV populations into three distinct fractions. Nanoparticle tracking analysis and transmission electron microscopy were used to validate their morphological characteristics, and bioinformatic analysis of LC-MS/MS proteomics corroborated cellular origins and function.
Proteomic data indicated potential novel proteic markers of -derived exosomes, including proteins involved in endosomal machinery and the ESCRT pathway, as well as the parasitic phosphatase PRL-1. Further investigation is required to determine the specificity and sensitivity of these markers.
细胞外囊泡 (EVs) 是异质的细胞来源的膜结合结构,根据不同的形态特征、细胞起源和功能,可以分为三个不同的类别。小 EVs,或外泌体,可以通过进化保守的 ESCRT 途径由原生动物寄生虫 产生,并作为哺乳动物宿主中毒力效应子和发病机制驱动因素发挥作用。然而,与特征明确的哺乳动物 EVs 相比,用于鉴定非哺乳动物来源的 EVs 的技术仍然不够准确。因此,我们仍然缺乏 衍生的外泌体的可靠和特异性标志物,这对该领域构成了重大挑战。
本文中,我们利用连续差速超速离心将 衍生的 EV 群体分离成三个不同的部分。纳米颗粒跟踪分析和透射电子显微镜用于验证其形态特征,LC-MS/MS 蛋白质组学的生物信息学分析证实了细胞起源和功能。
蛋白质组学数据表明 衍生的外泌体的潜在新型蛋白标志物,包括参与内体机制和 ESCRT 途径的蛋白,以及寄生虫磷酸酶 PRL-1。需要进一步研究来确定这些标志物的特异性和敏感性。