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Production of a cytotoxin by Helicobacter pylori

R D Leunk1

  • 1Procter & Gamble Company, Miami Valley Laboratories, Cincinnati, Ohio 45239-8707.

Reviews of Infectious Diseases
|July 1, 1991
PubMed

Insights

Helicobacter pylori produces a unique cytotoxin that causes cell vacuolation. This toxin is linked to peptic ulcers, suggesting it contributes to disease severity in H. pylori infections.

Area of Science:

  • Microbiology
  • Cell Biology
  • Pathogenesis

Background:

  • Helicobacter pylori is a bacterium associated with gastrointestinal diseases.
  • A cytotoxin produced by H. pylori was initially identified by its effect on cultured cells.

Purpose of the Study:

  • To characterize the H. pylori cytotoxin.
  • To determine the prevalence and in vivo relevance of the cytotoxin.
  • To investigate the association of the cytotoxin with disease severity.

Main Methods:

  • Culturing H. pylori isolates.
  • Assessing cytotoxin activity via cell vacuolation.
  • Protein characterization studies.
  • Detection of serum antibodies using neutralization and immunoblotting.

Main Results:

  • Fifty-three percent of over 200 H. pylori isolates produced the cytotoxin.
  • The cytotoxin is a high-molecular-weight protein unique to H. pylori.
  • Antibodies to the cytotoxin were detected in patient sera, indicating in vivo production.
  • The cytotoxin was more frequent in peptic ulcer cases than gastritis cases.

Conclusions:

  • H. pylori produces a distinct cytotoxin that is immunogenic in vivo.
  • This cytotoxin is associated with more severe H. pylori-related disease, specifically peptic ulceration.

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