title: Secreted protein HP1286 of Helicobacter pylori strain 26695 induces apoptosis of AGS cells.
abstract: OBJECTIVE
  Secreted proteins of Helicobacter pylori (H. pylori) interact with gastric epithelium cells and may contribute to cell damage. Considering the fact that HP0175 and hypothetical conserved protein HP1286 are included in the group and that HP0175 is a well-known apoptosis-induced factor, the present study aims to clarify whether HP1286 plays a role in bacterial pathogenicity or even functions as an apoptosis-induced factor in human stomach.
  
  
  METHODS
  Two genes encoding HP1286 and HP0175 were cloned into pET32a vector and expressed as recombinant proteins in Escherichia coli (E. coli) BL21. Signal peptide sequences were not included. The recombinant proteins were purified with His SpinTrap and desalted by using HiTrap Desalting. Immunoreactivity of the proteins was determined by Western blot. Human gastric epithelial cell AGS was challenged with these endotoxin-free proteins; and apoptosis of cells was assayed with the Cell Death ELISA kit.
  
  
  RESULTS
  Recombinant proteins and their respective products whose N-terminal his-tag were removed with thrombin were recognized by serum from the patient infected with H. pylori. Apoptotic AGS cells challenged by HP1286 of H. pylori 26695 were four times more than untreated cells. In addition, apoptosis-induced ability of HP1286 of SS1 was not as strong as that of H. pylori 26695 strain.
  
  
  CONCLUSIONS
  HP1286 of H. pylori 26695 induces apoptosis of AGS cells in a time-dependent manner, however the apoptosis-induced ability of HP1286 may differ due to variations between different strains.
authors.affiliation: National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Fan Liang
authors.initials: FL
authors.lastname: Meng
authors.forename: Li Hua
authors.initials: LH
authors.lastname: He
authors.forename: Jian Zhong
authors.initials: JZ
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D017209:Apoptosis / Q000187:drug effects*; D001426:Bacterial Proteins / Q000378:metabolism / Q000494:pharmacology*; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D014644:Genetic Variation; D016480:Helicobacter pylori / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D011994:Recombinant Proteins; D013274:Stomach Neoplasms
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins