Abstract
Background
The vacuolating cytotoxin and the cytotoxinassociated protein, encoded by vacA and cagA, respectively, are important virulence determinants of Helicobacter pylori.
Objective
The aim of this study was to perform vacA genotyping and evaluate its association with cagA genotype and clinical outcome.
Methods
One hundred and twenty H. pylori strains were isolated from dyspeptic patients (29 with peptic ulcer, 91 with non-ulcer dyspepsia). Genotype was determined by PCR.
Results
Seventy-nine (66%) of 120 strains had the vacA signal sequence genotype s1 and 41 (34%) had the type s2. The vacA middle-region types m1 and m2 were detected in 56 (47%) and 64 (53%) strains, respectively. The combinations s1-m1 (n=56 [47%] and s2-m2 (41 [34%]) occurred more frequently than s1-m2 (23 [19.2%]; p=0.001). No strain with the combination s2-m1 was found. All patients with peptic ulcers harbored type s1 strains compared to 75 (82.4%) of 91 patients with non-ulcer dyspepsia (p=0.01). The vacA genotype s1 was associated with the presence of cagA (p <0.0001). The cagA gene was detectable in 38 (31.6%) of 120 isolates and present in all 29 patients with ulcer compared to nine of 91 with non-ulcer dyspepsia (p <0.001).
Conclusion
Helicobacter pylori strains of vacA type s1 and the combination of s1-m1 were associated with peptic ulceration and the presence of cagA gene.
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References
Dunn BE, Cohen H, Blaser MJ. Helicobacter pylori. Clin Microbiol Rev 1997;10:720–741.
van Doorn LJ, Figueiredo C, Sanna R, et al. Clinical relevance of the cagA, vacA, and iceA status of Helicobacter pylori. Gastroenterology 1998;115:58–66.
Covacci A, Censini S, Bugnoli M, et al. Molecular characterization of the 128-kDa immunodominant antigen of Helicobacter pylori associated with cytotoxicity and duodenal ulcer. Proc Natl Acad Sci USA 1993;90:5791–5795.
Cover TL. The vacuolating cytotoxin of Helicobacter pylori. Mol Microbiol 1996;20:241–246.
Leunk RD. Production of a cytotoxin by Helicobacter pylori. Rev Infect Dis 1991;13(Suppl 8):S686–S689.
Atherton JC, Cao P, Peek RM, Jr., Tummuru MK, Blaser MJ, Cover TL. Mosaicism in vacuolating cytotoxin alleles of Helicobacter pylori. Association of specific vacA types with cytotoxin production and peptic ulceration. J Biol Chem 1995;270:17771–17777.
van Doorn LJ, Figueiredo C, Sanna R, et al. Expanding allelic diversity of Helicobacter pylori vacA. J Clin Microbiol 1998;36:2597–2603.
Censini S, Lange C, Xiang Z, et al. cag, a pathogenicity island of Helicobacter pylori, encodes type I-specific and disease-associated virulence factors. Proc Natl Acad Sci USA 1996;93:14648–14653.
Blaser MJ, Perez-Perez GI, Kleanthous H, et al. Infection with Helicobacter pylori strains possessing cagA is associated with an increased risk of developing adenocarcinoma of the stomach. Cancer Res 1995;55:2111–2115.
Kuipers EJ, Perez-Perez GI, Meuwissen SG, Blaser MJ. Helicobacter pylori and atrophic gastritis: importance of the cagA status. J Natl Cancer Inst 1995;87:1777–1780.
Atherton JC, Peek RM, Jr., Tham KT, Cover TL, Blaser MJ. Clinical and pathological importance of heterogeneity in vacA, the vacuolating cytotoxin gene of Helicobacter pylori. Gastroenterology 1997;112:92–99.
Strobel S, Bereswill S, Balig P, Allgaier P, Sonntag HG, Kist M. Identification and analysis of a new vacA genotype variant of Helicobacter pylori in different patient groups in Germany. J Clin Microbiol 1998;36:1285–1289.
Mukhopadhyay AK, Kersulyte D, Jeong JY, et al. Distinctiveness of genotypes of Helicobacter pylori in Calcutta, India. J Bacteriol 2000;182:3219–3227.
Pan ZJ, Berg DE, van der Hulst RW, et al. Prevalence of vacuolating cytotoxin production and distribution of distinct vacA alleles in Helicobacter pylori from China. J Infect Dis 1998;178:220–226.
Shimoyama T, Yoshimura T, Mikami T, Fukuda S, Crabtree JE, Munakata A. Evaluation of Helicobacter pylori vacA genotype in Japanese patients with gastric cancer. J Clin Pathol 1998;51:299–301.
Yamaoka Y, Kodama T, Gutierrez O, Kim JG, Kashima K, Graham DY. Relationship between Helicobacter pylori iceA, cagA, and vacA status and clinical outcome: studies in four different countries. J Clin Microbiol 1999;37:2274–2279.
Bindayna KM, Al Baker WA, Botta GA. Detection of Helicobacter pylori cagA gene in gastric biopsies, clinical isolates and faeces. Indian J Med Microbiol 2006;24:195–200.
Xiang Z, Censini S, Bayeli PF, et al. Analysis of expression of CagA and VacA virulence factors in 43 strains of Helicobacter pylori reveals that clinical isolates can be divided into two major types and that CagA is not necessary for expression of the vacuolating cytotoxin. Infect Immun 1995;63:94–98.
Ito Y, Azuma T, Ito S, et al. Analysis and typing of the vacA gene from cagA-positive strains of Helicobacter pylori isolated in Japan. J Clin Microbiol 1997;35:1710–1714.
Miehlke S, Kibler K, Kim JG, et al. Allelic variation in the cagA gene of Helicobacter pylori obtained from Korea compared to the United States. Am J Gastroenterol 1996;91:1322–1325.
Jaber SM. The pattern of CagA and VacA proteins in Helicobacter pylori seropositive asymptomatic children in western Saudi Arabia. Saudi Med J 2005;26:1372–1377.
Al Qabandi A, Mustafa AS, Siddique I, Khajah AK, Madda JP, Junaid TA. Distribution of vacA and cagA genotypes of Helicobacter pylori in Kuwait. Acta Trop 2005;93:283–288.
Alfaresi MS, Abdulsalam AI, Elkoush AA. Analysis of Helicobacter pylori antimicrobial susceptibility and virulence genes in gastric mucosal biopsies in the United Arab Emirates. Indian J Gastroenterol 2007;26:221–224.
Van Doorn LJ, Figueiredo C, Megraud F, et al. Geographic distribution of vacA allelic types of Helicobacter pylori. Gastroenterology 1999;116:823–830.
Wang HJ, Kuo CH, Yeh AA, Chang PC, Wang WC. Vacuolating toxin production in clinical isolates of Helicobacter pylori with different vacA genotypes. J Infect Dis 1998;178:207–212.
Atherton JC, Cover TL, Twells RJ, Morales MR, Hawkey CJ, Blaser MJ. Simple and accurate PCR-based system for typing vacuolating cytotoxin alleles of Helicobacter pylori. J Clin Microbiol 1999;37:2979–2982.
Rudi J, Kolb C, Maiwald M, et al. Diversity of Helicobacter pylori vacA and cagA genes and relationship to VacA and CagA protein expression, cytotoxin production, and associated diseases. J Clin Microbiol 1998;36:944–948.
Akopyants NS, Clifton SW, Kersulyte D, et al. Analyses of the cag pathogenicity island of Helicobacter pylori. Mol Microbiol 1998;28:37–53.
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Bindayna, K.M., Al Mahmeed, A. vacA genotypes in Helicobacter pylori strains isolated from patients with and without duodenal ulcer in Bahrain. Indian J Gastroenterol 28, 175–179 (2009). https://doi.org/10.1007/s12664-009-0069-1
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DOI: https://doi.org/10.1007/s12664-009-0069-1