title: Exosomes Secreted by Toxoplasma gondii-Infected L6 Cells: Their Effects on Host Cell Proliferation and Cell Cycle Changes.
abstract: Toxoplasma gondii infection induces alteration of the host cell cycle and cell proliferation. These changes are not only seen in directly invaded host cells but also in neighboring cells. We tried to identify whether this alteration can be mediated by exosomes secreted by T. gondii-infected host cells. L6 cells, a rat myoblast cell line, and RH strain of T. gondii were selected for this study. L6 cells were infected with or without T. gondii to isolate exosomes. The cellular growth patterns were identified by cell counting with trypan blue under confocal microscopy, and cell cycle changes were investigated by flow cytometry. L6 cells infected with T. gondii showed decreased proliferation compared to uninfected L6 cells and revealed a tendency to stay at S or G2/M cell phase. The treatment of exosomes isolated from T. gondii-infected cells showed attenuation of cell proliferation and slight enhancement of S phase in L6 cells. The cell cycle alteration was not as obvious as reduction of the cell proliferation by the exosome treatment. These changes were transient and disappeared at 48 hr after the exosome treatment. Microarray analysis and web-based tools indicated that various exosomal miRNAs were crucial for the regulation of target genes related to cell proliferation. Collectively, our study demonstrated that the exosomes originating from T. gondii could change the host cell proliferation and alter the host cell cycle.
authors.affiliation: Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Min Jae
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Bong-Kwang
authors.initials: BK
authors.lastname: Jung
authors.affiliation: Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul 03080, Korea.|Korean Association of Health Promotion, Seoul 07649, Korea.
authors.forename: Jaeeun
authors.initials: J
authors.lastname: Cho
authors.affiliation: Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul 03080, Korea.|Korean Association of Health Promotion, Seoul 07649, Korea.
authors.forename: Hyemi
authors.initials: H
authors.lastname: Song
authors.affiliation: JE-UK laboratory of Molecular Cancer Therapeutics, Yonsei Cancer Institute, Yonsei University College of Medicine, Seoul 03722, Korea.
authors.forename: Kyung-Ho
authors.initials: KH
authors.lastname: Pyo
authors.affiliation: JE-UK laboratory of Molecular Cancer Therapeutics, Yonsei Cancer Institute, Yonsei University College of Medicine, Seoul 03722, Korea.
authors.forename: Ji Min
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Korean Centers for Disease Control and Prevention, Osong 28159, Korea.
authors.forename: Min-Kyung
authors.initials: MK
authors.lastname: Kim
authors.affiliation: Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul 03080, Korea.|Korean Association of Health Promotion, Seoul 07649, Korea.
authors.forename: Jong-Yil
authors.initials: JY
authors.lastname: Chai
mesh_terms: D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation; D055354:Exosomes / Q000378:metabolism*; D005434:Flow Cytometry; D006790:Host-Parasite Interactions; D059566:M Phase Cell Cycle Checkpoints / Q000502:physiology*; D035683:MicroRNAs / Q000096:biosynthesis*; D051381:Rats; D059807:S Phase Cell Cycle Checkpoints / Q000502:physiology*; D014122:Toxoplasma / Q000378:metabolism* / Q000472:pathogenicity; D014123:Toxoplasmosis / Q000469:parasitology / Q000473:pathology*
chemical_list: D035683:MicroRNAs
keywords: L6 cell; Toxoplasma gondii; cell cycle; exosome; proliferation