Characterization of a shiga-toxin 1-resistant stock of vero cells.
Shiga toxins (Stxs, also referred to as verotoxins) were first described as a novel cytotoxic activity against Vero cells. In this study, we report the characterization of an Stx1-resistant (R-) stock of Vero cells. (1) When the susceptibility of R-Vero cells to Stx1 cytotoxicity was compared to that of Stx1-sensitive (S-) Vero cells by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, cell viability after 48-hr exposure to 10 pg/ml of Stx1 was greater than 80% and less than 15%, respectively. (2) Although both a binding assay of fluorescence-labeled Stx1 and lipid analysis indicated considerable expression of Gb3Cer, a functional receptor for Stxs, in both Vero cells, anti-Gb3Cer monoclonal antibodies capable of binding to S-Vero cells failed to effectively label R-Vero cells, suggesting a conformational difference in the Gb3Cer expressed on R-Vero cells. (3) The lipid analysis also showed that the R-Vero cells contained significant amounts of Gb4Cer. In addition, introduction of exogenous Gb4Cer into S-Vero cells slightly inhibited Stx1 cytotoxicity, suggesting some correlation between glycosphingolipid composition and Stx1 resistance. (4) Both butyrate treatment and serum depression eliminated the Stx1 resistance of R-Vero cells. (5) The results of the analysis by confocal microscopy suggest a difference in intracellular transport of Stx1 between R-Vero and S-Vero cells. Further study of R-Vero cells may provide a model of Stx1 resistance via distinct intracellular transport of Stx1.
Sekino
Takaomi
T
Department of Developmental Biology, National Research Institute for Child Health and Development, Tokyo, Japan.
Kiyokawa
Nobutaka
N
Taguchi
Tomoko
T
Takenouchi
Hisami
H
Matsui
Jun
J
Tang
Wei-Ran
WR
Suzuki
Toyo
T
Nakajima
Hideki
H
Saito
Masahiro
M
Ohmi
Kazuhiro
K
Katagiri
Yohko U
YU
Okita
Hajime
H
Nakao
Hiroshi
H
Takeda
Tae
T
Fujimoto
Junichiro
J
D000818:Animals; D002087:Butyrates / Q000494:pharmacology; D002470:Cell Survival; D002522:Chlorocebus aethiops; D003603:Cytotoxins / Q000378:metabolism / Q000633:toxicity*; D005915:Globosides / Q000032:analysis; D018613:Microscopy, Confocal; D021381:Protein Transport; D022622:Shiga Toxin 1 / Q000378:metabolism / Q000633:toxicity*; D014281:Trihexosylceramides / Q000032:analysis / Q000276:immunology; D014709:Vero Cells
D002087:Butyrates; D003603:Cytotoxins; D005915:Globosides; D022622:Shiga Toxin 1; D014281:Trihexosylceramides; C024032:globotetraosylceramide; C018549:globotriaosylceramide