title: Identification of Legionella londiniensis isolated from hot spring water samples in Shizuoka, Japan, and cytotoxicity of isolates.
abstract: As part of an epidemiological study on legionellosis, we attempted to isolate Legionella spp. from hot spring water and were able to isolate L. londiniensis HYKF-90505 (=JCM 16338), confirming that L. londiniensis inhabits hot spring water in Japan. To investigate the disease potential of L. londiniensis, we examined its ability to grow intracellularly within Acanthamoeba sp. JAC/E1 strain. The isolated HYKF-90505 was able to grow within Acanthamoeba sp. JAC/E1 strain, and we confirmed also that the HYKF-90505 strain showed cytotoxicity for cultured cells such as J774.1 (JCRB0018). However, in a culture of human U937 cells, the bacterial count was not increased by the intracellular growth of the HYKF-90505 strain. Cells infected for 24 h and stained using the Giménez method showed no intracellular growth of the HYKF-90505 strain. Thus, the isolate appears to be weakly pathogenic to humans.
authors.affiliation: School of Life and Environmental Science, Azabu University, 1-17-71 Fuchinobe, Chuuo-ku, Sagamihara, Kanagawa, 252-5201, Japan. furuhata@azabu-u.ac.jp
authors.forename: Katsunori
authors.initials: K
authors.lastname: Furuhata
authors.forename: Kikumi
authors.initials: K
authors.lastname: Ogihara
authors.forename: Naoto
authors.initials: N
authors.lastname: Ishizaki
authors.forename: Kenji
authors.initials: K
authors.lastname: Oonaka
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Keiichi
authors.initials: K
authors.lastname: Goto
authors.forename: Motonobu
authors.initials: M
authors.lastname: Hara
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Miyamoto
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Yoshida
authors.forename: Masafumi
authors.initials: M
authors.lastname: Fukuyama
mesh_terms: D000048:Acanthamoeba / Q000382:microbiology; D045482:Hot Springs / Q000382:microbiology*; D006801:Humans; D042541:Intracellular Space / Q000382:microbiology; D007564:Japan; D007875:Legionella / Q000302:isolation & purification* / Q000472:pathogenicity; D020298:U937 Cells; D014871:Water Microbiology