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The Role of Cathepsin X in Infection With the Helicobacter Pylori

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified March 2010 by University Medical Centre Ljubljana.
Recruitment status was:  Recruiting
Information provided by:
University Medical Centre Ljubljana Identifier:
First received: June 2, 2010
Last updated: July 9, 2010
Last verified: March 2010
The immune response to Helicobacter pylori (Hp) importantly determines the pathogenesis of infection as well as the success of antibiotic eradication of the bacteria. The investigators want to demonstrate the importance of cathepsin X (CTSX), a cysteine protease, for the Hp eradication success. The diversity of the innate immune response to H. pylori antigens leading to either successful eradication of the infection or maintenance of chronic inflammation is connected to CTSX. The aim of this study is to determine whether H. pylori suppresses the CTSX expression and cytokine secretion in macrophage cell line THP-1 in the individuals that are not capable of eradicating the infection, opposite to H pylori in patients with successful H pylori eradication . The investigators also investigate the possibility whether strain-dependent differences in H. pylori lipopolysaccharide (LPS) influence the CTSX expression and cytokine secretion.

Condition Intervention
Persistence of Infection With Helicobacter Pylori
Drug: clarithromycin, metronidazole, proton pump inhibitor

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Prospective
Official Title: Helicobacter Pylori and Gastric Cancer - the Role of Cytokine Polymorphism, Cytokine Expression and Expression of TLR on Persistence of Helicobacter Pylori Infection and Development of Gastric Cancer.

Resource links provided by NLM:

Further study details as provided by University Medical Centre Ljubljana:

Primary Outcome Measures:
  • Evidence that cathepsin X influences on the eradication of Helicobacter pylori confirmed by lower expression of cathepsin X and cytokines in those patients. that can not eradicate Helicobacter pylori. [ Time Frame: 7 months after last participant included in the study ]
    The investigators assume that vast majority of patients, that have problems with eradication of Helicobater pylori, not caused by primary resistence to antibiotics, can not eradicate helicobacter because of inappropriate immune response. The investigators will measure cathepsin X (CTSX) expression and assume that those patients who have low concentrations of CTSX also have inappropriate immune response seen in low levels of cytokines. To treat such patients, you need to give them different and longer antibiotic therapy.

Biospecimen Retention:   Samples With DNA
Helicobacter pylori strains from patients are stored at -70oC.

Estimated Enrollment: 14
Study Start Date: November 2008
Estimated Study Completion Date: July 2010
Primary Completion Date: December 2009 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
H. pylori eradication failure
Those who eradicated Helicobacter pylori with appropriate antibiotic therapy and those who did not.
Drug: clarithromycin, metronidazole, proton pump inhibitor
appropriate dose of antibiotics and proton pump inhibitor
Other Name: No other names


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
The investigators invited people who had problems with H. pylori(Hp) infection. They were tested for Hp and if positive they were enrolled in the study.All patients were treated with appropriate therapy.3 months after antibiotic therapy, the patients were re-examined. The patients that had a positive test were invited to another re-evaluation.If H. pylori sensitive to all antibiotics tested was isolated, we enrolled the patient in the study-7 patients. The investigators took the patient's first isolate and used it to prepare antigens for the study. All patients in the control group, 7 patients, were successfully cured with first attempt of antimicrobial therapy.Seven months after last patient enrolled, all the participants will be re-evaluated to see if they are still infected with Hp.

Inclusion Criteria:People with helicobacter gastritis and Helicobacter sensitive to antibiotic therapy but failure of therapy -

Exclusion Criteria:People with helicobacter gastritis who did not eradicate Helicobacter pylori because of primary resistance to antibiotics.

  Contacts and Locations
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Please refer to this study by its identifier: NCT01137942

Contact: Alojz Ihan, MD, PhD 0038615437493
Contact: Miha Skvarc, MD 0038615437484

Abakus Medico Recruiting
Rogaska Slatina, Slovenia
Contact: Bojan Tepes, MD. PhD    +386 (0) 3 819 14 11   
Principal Investigator: Bojan Tepes, MD, Phd         
Sub-Investigator: Miha Skvarc, MD         
Sponsors and Collaborators
University Medical Centre Ljubljana
Study Director: Alojz Ihan, MD, PhD Institute of microbiology and immunology, Ljubljana, Slovenia
  More Information

Responsible Party: Srecko Koren, Institute of microbiology and immunology, Medical faculty Ljubljana, Slovenia Identifier: NCT01137942     History of Changes
Other Study ID Numbers: IMI2010-1
1000-05-310123 ( Other Grant/Funding Number: Slovenian Research Agency (ARRS) )
Study First Received: June 2, 2010
Last Updated: July 9, 2010

Keywords provided by University Medical Centre Ljubljana:
helicobacter pylori
eradication failure

Additional relevant MeSH terms:
Communicable Diseases
Proton Pump Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Anti-Infective Agents
Antiprotozoal Agents
Antiparasitic Agents
Anti-Bacterial Agents
Protein Synthesis Inhibitors
Cytochrome P-450 CYP3A Inhibitors
Cytochrome P-450 Enzyme Inhibitors processed this record on April 25, 2017