Helicobacter pylori Strains from Duodenal Ulcer Patients Exhibit Mixed babA/B Genotypes with Low Levels of BabA Adhesin and Lewis b Binding.
Dig Dis Sci
; 61(10): 2868-2877, 2016 10.
Article
en En
| MEDLINE
| ID: mdl-27318698
ABSTRACT
BACKGROUND:
BabA is a Helicobacter pylori cell surface adhesin, which binds to the ABO/Le(b) histo-blood group antigens (Le(b)) and serves as a virulence factor.METHODS:
H. pylori single colonies were isolated from 156 [non-ulcer dyspepsia (NUD) = 97, duodenal ulcer (DU) = 34, gastric cancer (GC) = 25)] patients. babA and babB genes were evaluated by gene/locus-specific PCR. BabA protein expression and Le(b) binding activity were determined by immunoblotting and ELISA, respectively.RESULTS:
The combined categorization of H. pylori strains based on high, low or no levels of BabA expression and Le(b) binding, produced 4 groups (I) BabA-high/Le(b)-high (36 %), (II) BabA-low/Le(b)-low (26 %), (III) BabA-neg/Le(b)-low (30 %) and (IV) BabA-neg/Le(b)-neg (8 %) strains. The majority (63 %) of the BabA-low/Le(b)-low strains exhibited mixed babA/B genotypes as compared to merely 18 % of the BabA-high/Le(b)-high, 15 % of the BabA-neg/Le(b)-neg and 11 % of the BabA-neg/Le(b)-low (P = 0.0001) strains. In contrast to NUD strains, the great majority (70 %) of DU strains were BabA-low/Le(b)-low (11 %, P = 0.0001), which compared to NUD strains, enhanced the risk of DU by 18.8-fold. In parallel, infection with babA/B mixed genotype strains amplified the risk of DU by 3.6-fold (vs. babA-positive P = 0.01) to 6.9-fold (vs. babA-negative P = 0.007).CONCLUSIONS:
Here, we show higher prevalence of mixed babA/B genotypes among BabA-low/Le(b)-low clinical strains. Recombination of babA and babB genes across their loci may yield lower BabA expression and lower Le(b) binding activity. We conclude that H. pylori strains with lower Le(b) binding activity are better adapted for colonization of the gastric metaplastic patches in the duodenum and enhance the risk of duodenal ulcers.Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas de la Membrana Bacteriana Externa
/
Helicobacter pylori
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Infecciones por Helicobacter
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Adhesinas Bacterianas
/
Úlcera Duodenal
Tipo de estudio:
Risk_factors_studies
Límite:
Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Dig Dis Sci
Año:
2016
Tipo del documento:
Article
País de afiliación:
Irán