Molecular Typing of Helicobacter pylori by Virulence‐Gene Based Multiplex PCR and RT‐PCR Analysis

Abstract

The multiplex PCR and RT-PCR assay described allows rapid characterisation of H. pylori virulence genes at the DNA and RNA (cDNA) levels. However, extensive DNA sequence analysis seems necessary if one wants to reveal details of mutations occurring in the cagA and vacA genes.

Helicobacter pylori Multiplex Serology

“…The only protein showing significant serologic strain differences was VacA. Four polymorphic regions in VacA have been described: “s” and “m” [34,35], the repetitive hydrophilic motif [36] and the recently identified intermediate region [37]. The VacA genotype of strains 26695 and G27 that were used for VacA expression is s1m1.…”

Molecular biology methods for the characterization of Helicobacter pylori infections and their diagnosis

“…For example, PCR‐length polymorphism analysis may be used to assess the presence of absence of cagA (55). Multiplex PCR may be performed, whereby more than one primer pair may be used in a single reaction to assess several alleles at once (18, 56, 57). Product may be visualized by using agarose gel electrophoresis with subsequent ethidium bromide staining.…”

Assessment of the mosaic structure in the Helicobacter pylori cagA gene 3′-region using an improved polymerase chain reaction–based assay

“…They have shown that strains with an 18 bp or 39 bp deletion in the pre-EPIYA/T region possessed an EPIYA/T-D segment, whereas strains without any deletion commonly had an EPIYA/T-C segment [13]. In this study we used DNA isolated from 24 archival Helicobacter pylori strains (HJM1-18, 20-25), originally obtained from a routine clinical screening of non-ulcer dyspeptic (NUD) gastric biopsy specimens (mixed age and gender) collected at the Department of Clinical Microbiology, University Hospital Linköping Sweden [14]. Reference strain H. pylori 26695…”

“…H. pylori strains were cultured using an established clinical routine procedure [15]. Bacterial DNA was extracted [14], followed by multiple displacement amplification (MDA) using an Illustra GenomiPhi V2 DNA kit according to the manufacturer's instruction (GE-Healthcare, Uppsala, Sweden). Prior to MDA-amplification, the integrity of the bacterial DNA was analysed by 16S rDNA amplification as described elsewhere [16].…”