title: Cytolethality of hemolytic Escherichia coli to primary human renal proximal tubular cell cultures obtained from different donors.
abstract: OBJECTIVE
  In earlier experiments, we confirmed epidemiologic studies demonstrating the prominence in acute pyelonephritis of Escherichia coli expressing P fimbriae and hemolysin, produced the disease with pyelonephritogenic strains in an animal model, and developed in vitro assays using human renal proximal tubular cells that demonstrated bacterial adherence by P fimbriae and killing of the renal cells by hemolysin. In the present series of experiments, we sought to determine whether P-fimbriated hemolytic E coli killed human renal proximal tubular epithelial cells obtained from different human donors.
  
  
  METHODS
  Human renal proximal tubular cells, putative target cells for bacteria causing acute pyelonephritis, were cultured from 9 donors and cell death was measured by two methods.
  
  
  RESULTS
  We showed that the E coli strain was significantly more cytolethal for renal cells of all donors than its hemolysin-negative mutant.
  
  
  CONCLUSIONS
  This work suggests that the pathogenesis of acute pyelonephritis by P-fimbriated hemolytic E coli, characteristics of the causative organism in about 50% of human cases, may be at least in part through killing of human renal epithelial cells by hemolysin.
authors.affiliation: Department of Medicine, University of Maryland School of Medicine, Baltimore, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Warren
authors.forename: H L
authors.initials: HL
authors.lastname: Mobley
authors.forename: J R
authors.initials: JR
authors.lastname: Hebel
authors.forename: A L
authors.initials: AL
authors.lastname: Trifillis
mesh_terms: D002470:Cell Survival; D002478:Cells, Cultured; D004926:Escherichia coli / Q000378:metabolism*; D010861:Fimbriae, Bacterial; D006460:Hemolysin Proteins / Q000096:biosynthesis / Q000502:physiology*; D006801:Humans; D007223:Infant; D007687:Kidney Tubules, Proximal / Q000166:cytology*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009499:Neutral Red / Q000494:pharmacology
chemical_list: D006460:Hemolysin Proteins; D009499:Neutral Red; D007770:L-Lactate Dehydrogenase