Alpha-hemolysin of uropathogenic Escherichia coli induces GM-CSF-mediated acute kidney injury

Mucosal Immunol. 2020 Jan;13(1):22-33. doi: 10.1038/s41385-019-0225-6. Epub 2019 Nov 12.

Abstract

Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections (UTIs), inducing acute pyelonephritis and may result in permanent renal scarring and failure. Alpha-hemolysin (HlyA), a key UPEC toxin, causes serious tissue damage; however, the mechanism through which HlyA induces kidney injury remains unclear. In the present study, granulocyte-macrophage colony-stimulating factor (GM-CSF) secreted by renal epithelial cells was upregulated by HlyA in vitro and in vivo, which induced M1 macrophage accumulation in kidney, and ADAM10 was found involved in HlyA-induced GM-CSF. Macrophage elimination or GM-CSF neutralization protected against acute kidney injury in mice, and increased GM-CSF was detected in urine of patients infected by hlyA-positive UPEC. In addition, HlyA was found to promote UPEC invasion into renal epithelial cells by interacting with Nectin-2 in vitro. However, HlyA did not affect bacterial titers during acute kidney infections, and HlyA-induced invasion did not contribute to GM-CSF upregulation in vitro, which indicate that HlyA-induced GM-CSF is independent of bacteria invasion. The role of GM-CSF in HlyA-mediated kidney injury may lead to novel strategies to treat acute pyelonephritis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Kidney Injury / metabolism*
  • Acute Kidney Injury / microbiology
  • Animals
  • Disease Models, Animal
  • Epithelial Cells / metabolism*
  • Epithelial Cells / pathology
  • Escherichia coli / physiology*
  • Escherichia coli Infections / metabolism*
  • Escherichia coli Infections / microbiology
  • Escherichia coli Proteins / metabolism*
  • Female
  • Gene Expression Regulation
  • Granulocyte-Macrophage Colony-Stimulating Factor / metabolism
  • Hemolysin Proteins / metabolism*
  • Humans
  • Kidney / pathology*
  • Mice
  • Mice, Inbred C57BL
  • Nectins / metabolism
  • Pyelonephritis / metabolism*
  • Pyelonephritis / microbiology
  • Signal Transduction
  • Urinary Tract Infections

Substances

  • Escherichia coli Proteins
  • Hemolysin Proteins
  • Hlya protein, E coli
  • Nectins
  • Granulocyte-Macrophage Colony-Stimulating Factor