Open AccessEffects of interaction between Escherichia coli verotoxin and lipopolysaccharide on cytokine induction and lethality in mice
Author(s) -
Kuri Suzuki,
Kazuhiro Tateda,
Tetsuya Matsumoto,
Fumio Gondaira,
Shirou Tsujimoto,
Keizo Yamaguchi
Publication year - 2000
Publication title -
journal of medical microbiology/journal of medical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.91
H-Index - 117
eISSN - 1473-5644
pISSN - 0022-2615
DOI - 10.1099/0022-1317-49-10-905
Subject(s) - lipopolysaccharide , cytokine , escherichia coli , tumor necrosis factor alpha , lethality , interleukin , lethal dose , median lethal dose , biology , ratón , toxicity , microbiology and biotechnology , immunology , pharmacology , medicine , biochemistry , toxicology , gene
In Escherichia coli 0157 infections, verotoxins (VT) play a critical role in causing the disease, although other factors such as lipopolysaccharide (LPS) and inflammatory cytokines may affect the progression and course of the disease. The present study examined the roles of VT and LPS in induction of serum cytokines and lethality in mice. LD50 of VT2 (13 ng) was c. 10(4)-fold smaller than that of LPS (400 microg). Although the lethal toxicity of these toxins was examined in several experimental conditions, such as VT2 (5, 10, 20, 40 ng/mouse) alone or in combination with LPS (100 microg/mouse) at various times (-2 days to +2 days), no evidence of synergy was observed. VT2 did not augment LPS-induced tumour necrosis factor-alpha (TNF-alpha) or interleukin-6 production, and conversely suppressed TNF-alpha production when it was injected 2 days before LPS challenge. The data failed to indicate either synergic or additive effects of VT and LPS on cytokine production or lethality in mice. In contrast, antagonistic interactions were clearly observed in cytokine production in certain conditions. The results suggested that these toxins may be co-operatively involvedin the pathology of VT-related diseases, but not through synergic interactions.