Contribution of adenosine A(2B) receptors in Clostridium difficile intoxication and infection

Infect Immun. 2012 Dec;80(12):4463-73. doi: 10.1128/IAI.00782-12. Epub 2012 Oct 8.

Abstract

Clostridium difficile toxins A (TcdA) and B (TcdB) induce a pronounced systemic and intestinal inflammatory response. A(2B) adenosine receptors (A(2B)ARs) are the predominant adenosine receptors in the intestinal epithelium. We investigated whether A(2B)ARs are upregulated in human intestinal cells by TcdA or TcdB and whether blockade of A(2B)ARs can ameliorate C. difficile TcdA-induced enteritis and alter the outcome of C. difficile infection (CDI). Adenosine receptor subtype (A(1), A(2A), A(2B), and A(3)) mRNAs were assayed in HCT-8 cells. Ileal loops from wild-type rabbits and mice and A(2B)AR(-/-) mice were treated with TcdA, with or without the selective A(2B)AR antagonist ATL692 or PSB1115. A murine model of CDI was used to determine the effect of A(2B)AR deletion or blockade with the orally available agent ATL801, on clinical outcome, histopathology and intestinal interleukin-6 (IL-6) expression from infection. TcdA and TcdB upregulated A(2B)AR gene expression in HCT-8 cells. ATL692 decreased TcdA-induced secretion and epithelial injury in rabbit ileum. Deletion of A(2B)ARs reduced secretion and histopathology in TcdA-challenged mouse ileum. Deletion or blockade of A(2B)ARs reduced histopathology, IL-6 expression, weight loss, diarrhea, and mortality in C. difficile-infected mice. A(2B)ARs mediate C. difficile toxin-induced enteritis and disease. Inhibition of A(2B)AR activation may be a potential strategy to limit morbidity and mortality from CDI.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Proteins / pharmacology
  • Bacterial Toxins / pharmacology
  • Cell Line, Tumor
  • Clostridioides difficile / genetics
  • Clostridioides difficile / metabolism
  • Clostridioides difficile / pathogenicity*
  • Colon* / microbiology
  • Colon* / pathology
  • Disease Models, Animal
  • Enterocolitis, Pseudomembranous* / microbiology
  • Enterocolitis, Pseudomembranous* / pathology
  • Enterotoxins / pharmacology
  • Gene Expression Regulation
  • Humans
  • Ileum / microbiology
  • Ileum / pathology
  • Mice
  • Mice, Inbred C57BL
  • Rabbits
  • Receptor, Adenosine A2B / genetics
  • Receptor, Adenosine A2B / metabolism*

Substances

  • Bacterial Proteins
  • Bacterial Toxins
  • Enterotoxins
  • Receptor, Adenosine A2B
  • tcdA protein, Clostridium difficile
  • toxB protein, Clostridium difficile