title: Bioactivity and immunological evaluation of LPS from different serotypes of Helicobacter pylori.
abstract: OBJECTIVE
  Helicobacter pylori is the causative agent of peptic ulcer disease and a co-factor in development of gastric malignancies. LPS are among toxic substances produced by H. pylori exhibiting low endotoxic activity compared to typical bacterial LPS. The aim of this study was to investigate bioactivity of LPS produced by different serotypes of Helicobacter pylori compared to Escherichia coli and Brucella abortus LPS.
  
  
  METHODS
  Bacterial LPS was extracted by the hot phenol-water method. Biological activities of LPS were determined via the limulus lysate assay, pyrogenic assay, and blood pressure and PBMC induction test in rabbits.
  
  
  RESULTS
  Biological activity of O2 serotype LPS of H. pylori was less than the biological activity of other H. pylori serotypes.
  
  
  CONCLUSIONS
  Our data supported the hypothesis that the unique bacterial LPS of the O2 serotype must be included in the formulation of a multivalent H. pylori vaccine.
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran ; Department of Bacteriology, Faculty of Medical Sciences, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Davoud
authors.initials: D
authors.lastname: Esmaeilli
authors.forename: Ashraf Mohabati
authors.initials: AM
authors.lastname: Mobarez
authors.forename: Ali Hatef
authors.initials: AH
authors.lastname: Salmanian
authors.forename: Ahmad Zavaran
authors.initials: AZ
authors.lastname: Hosseini
keywords: Bioactivity; H. pylori; LPS