Characterization of exosome-like vesicles derived from Taenia pisiformis cysticercus and their immunoregulatory role on macrophages

• Published in: Parasites & vectors Vol. 13; no. 1; p. 318
• Main Authors: Wang, Li-Qun, Liu, Ting-Li, Liang, Pan-Hong, Zhang, Shao-Hua, Li, Tao-Shan, Li, Yan-Ping, Liu, Guang-Xue, Mao, Li, Luo, Xue-Nong
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 19.06.2020; BioMed Central; BMC
• Subjects: Animals; Biogenesis; Breeding; Cellular signal transduction; Cysticercus - immunology; Cysticercus - parasitology; Cysticercus pisiformis; Cysts; Cytokines; Cytokines - metabolism; Data analysis; Defence mechanisms; Economic impact; Economics; Electron microscopy; ELISA; Encyclopaedias; Encyclopedias; Enzyme-linked immunosorbent assay; Enzymes; Exosome-like vesicles; Exosomes - metabolism; Exosomes - ultrastructure; Gene sequencing; Genomes; Genomics; Helminth Proteins - metabolism; Host-Parasite Interactions; Identification; Immune response; Immune system; Immunity; Immunology; Immunomodulation; Immunoregulation; Infections; Interleukin 10; Interleukin 12; Interleukin 13; Interleukin 4; Interleukin 6; Intestinal parasites; Intestine; Laboratory animals; Lymphocytes T; Macrophages; Macrophages - immunology; Mass spectrometry; Mice; MicroRNA; MicroRNAs - metabolism; Morphology; Nanoparticles; Nitric-oxide synthase; Nucleic acids; Ontology; Parasites; Penicillin; Peptides; Proteins; Rabbits; RAW 264.7 Cells; Ribonucleic acid; RNA; RNA sequencing; RNA, Helminth - metabolism; Scientific imaging; Secretory products; Secretory vesicles; Signal transduction; Software; Taenia - metabolism; Taenia - physiology; Taenia pisiformis; Th2-type immune response; Transmission electron microscopy; Ultracentrifugation; Vesicles; γ-Interferon; United Kingdom; China; New Zealand; United Kingdom > UK; United States > US; Th2-type immune response; Cysticercus pisiformis; Macrophages; Exosome-like vesicles
• ISSN: 1756-3305; 1756-3305
• DOI: 10.1186/s13071-020-04186-z

Taenia pisiformis is one of the most common intestinal parasites in canines, and leads to serious economic losses in the rabbit breeding industry. Exosome-like vesicles from parasites play crucial roles in host-parasite interactions by transferring cargo from parasites to host cells and by modulating host immunological response through inducing production of host-derived cytokines. Nevertheless, the mechanism by which exosome-like vesicles from T. pisiformis cysticercus regulate the macrophage immune response remains unknown. Using ultracentrifugation, we isolated exosome-like vesicles from excretory/secretory products (ESP) of T. pisiformis cysticercus. The morphology and size of purified vesicles were confirmed by transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). The components of proteins and miRNAs within these vesicles were identified by proteomic analysis and high-throughput small RNA sequencing. The biological function of targets of exosomal miRNAs was predicted by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Moreover, the expression of Th1- and Th2-type immune response associated cytokines in RAW264.7 macrophages were evaluated by qPCR and ELISA. We found that exosome-like vesicles were typical cup-shaped vesicles with diameters from 30 to 150 nm. A total of 87 proteins were identified by proteomic analysis, including proteins prominently associated with exosome-like vesicles biogenesis and vesicle trafficking. 41 known miRNAs and 18 novel miRNAs were identified in the exosome-like vesicles. Eleven selected miRNAs, including 7 known miRNAs (miR-71-5p, miR-10a-5p, miR-let-7-5p, miR-745-3p, miR-219-5p, miR-124-3p and miR-4989-3p) and 4 novel miRNAs (novel-mir-3, novel-mir-7, novel-mir-8 and novel-mir-11) were validated to exist in metacestiodes and exosome-like vesicles of T. pisiformis cysticercus by qPCR. The functions of most targets of exosomal miRNAs were mainly associated with signal transduction and the immune system. Additionally, T. pisiformis cysticercus-derived vesicles induced the production of IL-4, IL-6, IL-10, IL-13 and Arg-1, but downregulated the expression of IL-12, IFN-γ and iNOS in RAW264.7 macrophages. We demonstrated that proteins and miRNAs enclosed within exosome-like vesicles from T. pisiformis cysticercus have immunomodulatory functions. Furthermore, exosome-like vesicles were shown to induce the macrophage Th2-type immune response in vitro. Our study suggests that exosome-like vesicles play an important role in the interaction between cysticerci and their hosts.