: Helicobacter pylori is an extremely common infection that causes gastritis and is clearly implicated in the development of peptic ulcer disease and gastric cancer. A full understanding of H. pylori pathogenesis requires an analysis of bacterial gene expression in vivo in a relevant animal model. The availability of the complete H. pylori genome sequence, together with novel technologies for measurement of gene expression, makes it possible to address this problem in the rhesus monkey model that we have recently developed at the California Regional Primate Research Center (CRPRC). We hypothesize that H. pylori genes important in virulence will be induced by contact with the host gastric epithelium. Furthermore, we propose that bacterial gene expression in the host will be modulated by the presence of the cagA pathogenicity island and by luxS, a gene implicated in quorum sensing. Specific pathogen free rhesus monkeys will be inoculated with wild type H. pylori or with isogenic mutants carrying deletions in the cagA pathogenicity island or in luxS. In vivo transcription in targeted genes will be measured by quantitative RT-PCR during a 6-month period of infection. The results in animals infected with wild type and mutant strains will be compared over time. Furthermore, we will compare changes in gene transcription between cells grown in vitro and those isolated in vivo. An understanding of the dynamic interaction between host and pathogen may point the way toward critical proteins that may be useful as targets for therapy or vaccine development.

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21RR015293-01A1
Application #
6400495
Study Section
Bacteriology and Mycology Subcommittee 2 (BM)
Program Officer
Grieder, Franziska B
Project Start
2001-06-20
Project End
2003-05-31
Budget Start
2001-06-20
Budget End
2002-05-31
Support Year
1
Fiscal Year
2001
Total Cost
$145,677
Indirect Cost
Name
University of California Davis
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
094878337
City
Davis
State
CA
Country
United States
Zip Code
95618
Boonjakuakul, Jenni K; Canfield, Don R; Solnick, Jay V (2005) Comparison of Helicobacter pylori virulence gene expression in vitro and in the Rhesus macaque. Infect Immun 73:4895-904
Boonjakuakul, Jenni K; Syvanen, Michael; Suryaprasad, Arun et al. (2004) Transcription profile of Helicobacter pylori in the human stomach reflects its physiology in vivo. J Infect Dis 190:946-56
Huff, Jennifer L; Hansen, Lori M; Solnick, Jay V (2004) Gastric transcription profile of Helicobacter pylori infection in the rhesus macaque. Infect Immun 72:5216-26
Solnick, Jay V (2003) Clinical significance of Helicobacter species other than Helicobacter pylori. Clin Infect Dis 36:349-54