Differentiation of Helicobacter pylori strains directly from gastric biopsy specimens by PCR-based restriction fragment length polymorphism analysis without culture

Abstract

Recent studies have shown the usefulness of PCR-based restriction fragment length polymorphism (RFLP) analysis for differentiating Helicobacter pylori strains isolated by culture. For this study, a PCR-based RFLP assay was developed for directly typing H. pylori strains from gastric biopsy specimens. Nineteen gastric biopsy specimens obtained from patients undergoing endoscopy for gastrointestinal complaints were cultured for isolation of H. pylori. Genomic DNA preparations from these gastric biopsy specimens and the corresponding H. pylori isolates were tested by our PCR-based RFLP assay. The 1,179-bp H. pylori DNA fragments amplified by the PCR assay were digested with the restriction enzymes HhaI, MboI, and AluI and analyzed by agarose gel electrophoresis. HhaI, MboI, and AluI digestion produced 11, 10, and 6 distinguishable digestion patterns, respectively, from the 19 H. pylori isolates tested and generated 13, 11, and 6 different patterns, respectively, from the 19 gastric biopsy specimens. The patterns from 13 of the 19 gastric biopsy specimens matched those of the H. pylori isolates from the corresponding patients. The patterns from the remaining six biopsy specimens appeared to represent infection by two strains of H. pylori; the pattern of one strain was identical to that of the isolate from the corresponding patient. By combining all the restriction enzyme digestion patterns obtained by using HhaI, MboI, and AluI, we observed 19 distinct RFLP patterns from the 19 specimens. The results suggest that the PCR-based RFLP analysis method may be useful as a primary technique to identify and distinguish H. pylori strains directly from gastric biopsy specimens without culture of the organisms.

Detection of Specific Helicobacter pylori DNA and Antigens in Stool Samples in Dyspeptic Patients and Healthy Subjects

“…Several studies have been performed to detect specific H. pylori genes in gastric biopsy specimens, dental plaque and saliva (3,7,15,16,26). The ureA, cagA and recently vacA genes were detected in gastric biopsies (3,7,16). An epidemiological value of the PCR tech-niques detecting H. pylori infections may be decreased by false-positive reactions due to contamination of gastroscopes with H. pylori DNA.…”

Different Helicobacter pylori Strains Colonize the Antral and Duodenal Mucosa of Duodenal Ulcer Patients

“…Previous studies have shown frequent genome diversity in H. pylori strains isolated from the stomach of ulcer patients [13][14][15][16]22]. With regard to phenotypic analysis, few studies have shown enough variation in antigen expression in H. pylori to reveal differentiation between strains correlating to disease [6,7].…”

“…Different chromosomal DNA and ribosomal RNA gene profiles have been demonstrated in H. pylori strains collected in clinical studies [13][14][15][16][17][18][19][20][21], using several fingerprinting and typing techniques, including random or specific polymerase chain reactions (PCRs), to determine genomic diversity.…”

Molecular fingerprinting of Helicobacter pylori strains from duodenal ulcer patients

“…The large degree of genetic variations among H. pylori strains can be detected using various molecular techniques such as restriction enzyme analysis based on PCR methods (Akyopyants et al 1992;Cellini et al 1996;Dzierzanowska et al 1996;Li et al 1997;Burucoa et al 1999). We report the use of a RAPD typing to detect DNA sequence diversity among H. pylori isolates.…”