Relationship of vacA genotypes of Helicobacter pylori to cagA status, cytotoxin production, and clinical outcome.

摘要: Background. Mosaicism in vacA alleles with three distinct families of signal sequences (s1a, s1b and s2) two middle region (m1 m2) has been reported. It was suggested that the s1a genotype closely associated duodenal ulcer disease high cytotoxin production. The aim this study to evaluate role genotyping respect gastric inflammation injury, activity, clinical presentation. Methods. H. pylori from patients gastritis, peptic disease, or cancer were characterized by typing polymerase chain reaction (PCR) DNA sequencing. In vitro activity assessed vacuolation assay using Vero cells as well Hela cells. Results. Four hundred ninety-one strains tested. s1a/m1 present more than 95% independent presentation ulcer, cancer. No average activity. s2/m2 isolates had low absent All cagA negative (n = 18) both positive. One strain a recombinant m1 m2 identified nucleotide amino acid between original Japanese (new strains) about 85% 81%, respectively. Strains new similarity 96%. There no difference Western type genotype. Conclusion. In other reported studies (≈ 1500 overall) strongly but not exclusively presence cagA. Overall, did support for relation virulence, histologic finding, risk particular H. disease. s1 is likely be surrogate marker cag pathogenicity island.