Lipopolysaccharide renders transgenic mice expressing human serum Amyloid P component sensitive to Shiga Toxin 2

Thomas P. Griener, Jonathan G. Strecker, Romney M. Humphries, George L. Mulvey, Carmen Fuentealba, Robert Hancock, Glen D. Armstrong

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Transgenic C57BL/6 mice expressing human serum amyloid P component (HuSAP) are resistant to Shiga toxin 2 (Stx2) at dosages that are lethal in HuSAP-negative wild-type mice. However, it is well established that Stx2 initiates extra-intestinal complications such as the haemolytic-uremic syndrome despite the presence of HuSAP in human sera. We now demonstrate that co-administering purified Escherichia coli O55 lipopolysaccharide (LPS), at a dosage of 300 ng/g body weight, to HuSAP-transgenic mice increases their susceptibility to the lethal effects of Stx2. The enhanced susceptibility to Stx2 correlated with an increased expression of genes encoding the pro-inflammatory cytokine TNFα and chemokines of the CXC and CC families in the kidneys of LPS-treated mice, 48 hours after the Stx2/LPS challenge. Co-administering the glucocorticoid dexamethasone, but not the LPS neutralizing cationic peptide LL-37, protected LPS-sensitized HuSAP-transgenic mice from lethal doses of Stx2. Dexamethasone protection was specifically associated with decreased expression of the same inflammatory mediators (CXC and CC-type chemokines and TNFα) linked to enhanced susceptibility caused by LPS. The studies reveal further details about the complex cascade of host-related events that are initiated by Stx2 as well as establish a new animal model system in which to investigate strategies for diminishing serious Stx2-mediated complications in humans infected with enterohemorrhagic E. coli strains.

Original languageEnglish
Article numbere21457
JournalPLoS ONE
Volume6
Issue number6
DOIs
Publication statusPublished - 30 Jun 2011
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)
  • General

Cite this

Griener, T. P., Strecker, J. G., Humphries, R. M., Mulvey, G. L., Fuentealba, C., Hancock, R., & Armstrong, G. D. (2011). Lipopolysaccharide renders transgenic mice expressing human serum Amyloid P component sensitive to Shiga Toxin 2. PLoS ONE, 6(6), [e21457]. https://doi.org/10.1371/journal.pone.0021457