title: Granulocyte-macrophage colony-stimulating factor (GM-CSF) is released by female mouse bladder urothelial cells and expressed by the urothelium as an early response to lipopolysaccharides (LPS).
abstract: OBJECTIVE
  We studied in vitro and in vivo response of primary mouse bladder urothelial cells (mBUC) and bladder urothelium to lipopolysaccharides (LPS), focusing on granulocyte-macrophage colony-stimulating factor (GM-CSF) signaling.
  
  
  METHODS
  Female C57BL/6 mBUC were exposed for 12 hr to differing concentrations of LPS (100 ng/ml to 10 µg/ml). mBUC were also exposed to a single dose of LPS (1 µg/ml) for 3, 6, 12 hr. Neutralizing GM-CSF antibody (0.1 μg/ml) was used block GM-CSF activity in vitro. In vivo experiments were performed, whereby, LPS (1 mg/ml) was instilled intravesically and left to dwell for 30 min followed by harvest of bladder urothelium 3 to 18 hr later. ELISA measured GM-CSF. qPCR quantitated mRNA for GM-CSF, vascular endothelial growth factor-A (VEGF-A), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and tumor necrosis factor α (TNF-α). RT-PCR was used to detect mRNA for GM-CSF, GM-CSFRα, and β in bladder tissues. Immunohistofluorescence and Western blots for GM-CSFRα were performed on bladder tissues.
  
  
  RESULTS
  LPS induced a dose-dependent release of GM-CSF by mBUC. Mouse bladder urothelium did not express GM-CSF mRNA at baseline, but expressed GM-CSF mRNA 3 hr after in vivo LPS exposure, with GM-CSF mRNA expression disappearing 18 hr later. GM-CSFRα expression was confirmed in bladder urothelium. GM-CSF neutralizing antibody significantly diminished LPS-induced increases of VEGF and COX-2 mRNA expression.
  
  
  CONCLUSIONS
  Urothelium and mBUC secreted GM-CSF as an early response to LPS. GM-CSF mediated downstream expression of VEGF and COX-2. Urothelial GM-CSF may function as a signaling mediator for both inflammation and pain transduction. Neurourol. Urodynam. 36:1020-1025, 2017. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Urology, Jinshan Hospital, Fudan University, Shanghai, China.|Department of Urology, Yale School of Medicine, New Haven, Connecticut.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Urology, Yale School of Medicine, New Haven, Connecticut.
authors.forename: Ming
authors.initials: M
authors.lastname: Lu
authors.affiliation: Department of Urology, Yale School of Medicine, New Haven, Connecticut.
authors.forename: Lery
authors.initials: L
authors.lastname: Alvarez-Lugo
authors.affiliation: Department of Urology, Jinshan Hospital, Fudan University, Shanghai, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: Department of Urology, Yale School of Medicine, New Haven, Connecticut.
authors.forename: Toby C
authors.initials: TC
authors.lastname: Chai
mesh_terms: D000283:Administration, Intravesical; D000818:Animals; D002478:Cells, Cultured; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis* / Q000378:metabolism; D008070:Lipopolysaccharides / Q000008:administration & dosage*; D051379:Mice; D008810:Mice, Inbred C57BL; D023421:Models, Animal; D001743:Urinary Bladder / Q000378:metabolism*; D019459:Urothelium / Q000378:metabolism*
chemical_list: D008070:Lipopolysaccharides; D016178:Granulocyte-Macrophage Colony-Stimulating Factor
keywords: GM-CSF; host defense; urinary tract infection; urothelium