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Variants of the 3' Region of the CagA Gene in Helicobacter Pylori Isolates from Patients with Different H. Pylori-associated Diseases

Overview
Specialty Microbiology
Date 1998 Jul 17
PMID 9666002
Citations 130
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Abstract

The CagA protein of Helicobacter pylori is an immunogenic antigen of variable size and unknown function that has been associated with increased virulence as well as two mutually exclusive diseases, duodenal ulcer and gastric carcinoma. The 3' region of the cagA gene contains repeated sequences. To determine whether there are structural changes in the 3' region of cagA that predict outcome of H. pylori infection, we examined 155 cagA gene-positive H. pylori isolates from Japanese patients including 50 patients with simple gastritis, 40 with gastric ulcer, 35 with duodenal ulcer, and 30 with gastric cancer. The 3' region of the cagA gene was amplified by PCR followed by sequencing. CagA proteins were detected by immunoblotting using a polyclonal antibody against recombinant CagA. One hundred forty-five strains yielded PCR products of 642 to 651 bp; 10 strains had products of 756 to 813 bp. The sequence of the 3' region of the cagA gene in Japan differs markedly from the primary sequence of cagA genes from Western isolates. Sequence analysis of the PCR products showed four types of primary gene structure (designated types A, B, C, and D) depending on the type and number of repeats. Six of the seven type C strains were found in patients with gastric cancer (P < 0.01 in comparison to noncancer patients). Comparison of type A and type C strains from patients with gastric cancer showed that type C was associated with higher levels of CagA antibody and more severe degrees of atrophy. Differences in cagA genotype may be useful for molecular epidemiology and may provide a marker for differences in virulence among cagA-positive H. pylori strains.

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References
1.
Sonnenberg A . The US temporal and geographic variations of diseases related to Helicobacter pylori. Am J Public Health. 1993; 83(7):1006-10. PMC: 1694789. DOI: 10.2105/ajph.83.7.1006. View

2.
Parsonnet J, Friedman G, ORENTREICH N, Vogelman H . Risk for gastric cancer in people with CagA positive or CagA negative Helicobacter pylori infection. Gut. 1997; 40(3):297-301. PMC: 1027076. DOI: 10.1136/gut.40.3.297. View

3.
Maeda S, Ogura K, Yoshida H, Kanai F, Ikenoue T, Kato N . Major virulence factors, VacA and CagA, are commonly positive in Helicobacter pylori isolates in Japan. Gut. 1998; 42(3):338-43. PMC: 1727030. DOI: 10.1136/gut.42.3.338. View

4.
Tummuru M, Cover T, Blaser M . Cloning and expression of a high-molecular-mass major antigen of Helicobacter pylori: evidence of linkage to cytotoxin production. Infect Immun. 1993; 61(5):1799-809. PMC: 280768. DOI: 10.1128/iai.61.5.1799-1809.1993. View

5.
Yamaoka Y, Kita M, Kodama T, Sawai N, Kashima K, Imanishi J . Induction of various cytokines and development of severe mucosal inflammation by cagA gene positive Helicobacter pylori strains. Gut. 1997; 41(4):442-51. PMC: 1891528. DOI: 10.1136/gut.41.4.442. View