title: Intracellular fate of Ureaplasma parvum entrapped by host cellular autophagy.
abstract: Genital mycoplasmas, including Ureaplasma spp., are among the smallest human pathogenic bacteria and are associated with preterm birth. Electron microscopic observation of U. parvum showed that these prokaryotes have a regular, spherical shape with a mean diameter of 146 nm. U. parvum was internalized into HeLa cells by clathrin-mediated endocytosis and survived for at least 14 days around the perinuclear region. Intracellular U. parvum reached endosomes in HeLa cells labeled with EEA1, Rab7, and LAMP-1 within 1 to 3 hr. After 3 hr of infection, U. parvum induced the cytosolic accumulation of galectin-3 and was subsequently entrapped by the autophagy marker LC3. However, when using atg7-/-MEF cells, autophagy was inadequate for the complete elimination of U. parvum in HeLa cells. U. parvum also colocalized with the recycling endosome marker Rab11. Furthermore, the exosomes purified from infected HeLa cell culture medium included U. parvum. In these purified exosomes ureaplasma lipoprotein multiple banded antigen, host cellular annexin A2, CD9, and CD63 were detected. This research has successfully shown that Ureaplasma spp. utilize the host cellular membrane compartments possibly to evade the host immune system.
authors.affiliation: Department of Developmental Medicine, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Fumiko
authors.initials: F
authors.lastname: Nishiumi
authors.affiliation: Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Michinaga
authors.initials: M
authors.lastname: Ogawa
authors.affiliation: Department of Developmental Medicine, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Nakura
authors.affiliation: Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hamada
authors.affiliation: Department of Pathology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nakayama
authors.affiliation: Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Mitobe
authors.affiliation: Critical Care Medical Center, Faculty of Medicine, Kindai University, Osaka, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hiraide
authors.affiliation: Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan.|Division of Health Science, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Sakai
authors.affiliation: Department of Pathology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Takeuchi
authors.affiliation: Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan.
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Yoshimori
authors.affiliation: Department of Developmental Medicine, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Itaru
authors.initials: I
authors.lastname: Yanagihara
mesh_terms: D000071182:Autophagosomes / Q000276:immunology* / Q000382:microbiology / Q000648:ultrastructure; D001343:Autophagy; D004847:Epithelial Cells / Q000276:immunology* / Q000382:microbiology / Q000648:ultrastructure; D006367:HeLa Cells; D054884:Host-Pathogen Interactions; D006801:Humans; D057131:Immune Evasion; D008854:Microscopy, Electron; D014509:Ureaplasma / Q000276:immunology* / Q000648:ultrastructure
keywords: Ureaplasma spp; autophagy; endocytosis; exosome; galectin