Rapid Detected and Diagnostic Assessment Vacuolating Cytotoxin A (vacA) Gene of Helicobacter pylori by Loop-Mediated Isothermal Amplification (LAMP)

Abstract

<jats:p>The loop-mediated isothermal amplification (LAMP) assay as efficient and convenient detection method was applied to detect the vacuolating cytotoxin A (<jats:italic>vacA</jats:italic>) gene of Helicobacter pylori (<jats:italic>H. pylori</jats:italic>). The extracted genomic DNA of <jats:italic>H. pylori</jats:italic>, which was purified through magnetic nanoparticles (MNPs), was amplified through the LAMP reaction using designed primers. The effect of LAMP detected on <jats:italic>H. pylori vacA</jats:italic> gene was evaluated through agarose gel electrophoresis in a gel imaging system and fluorescence-intensity analysis after addition of fluorescent dye. 11 pathogenic bacterial strains of different species were found to be negative for <jats:italic>vacA</jats:italic>, while only a single positive result was obtained for <jats:italic>H. pylori</jats:italic>. The minimum detection limit of the <jats:italic>vacA</jats:italic> gene was established as 100 fg. We used the primers with specificity and sensitivity, which were designed by the specificity analysis and sensitivity analysis system. Once developed, the LAMP assay was be used to the detection of the <jats:italic>vacA</jats:italic> gene in the gastric juice of patients. In conclusion, the LAMP assay is an efficient and fast tool for detection of the <jats:italic>H. pylori vacA</jats:italic> gene, and also for direct detection of the <jats:italic>vacA</jats:italic> gene in the gastric juice of patients, with high sensitivity and specificity. Most importantly, the proposed detection method shows promising potential for clinical application in the future, where it can greatly reduce the difficulty of detection and also shorten detection times.</jats:p>

Relationship between Helicobacter Pylori Morphological Forms in Gastric Biopsy and Helicobacter Pylori Stool Antigen

“…Coccoid forms are less virulent than spiral ones [11]. Additionally, they are also poorly responsive to antibiotic therapy [12]. H. pylori coccoid forms may be hidden within the biofilm (complex composed of bacteria and extracellular matrix of polyanionic polysaccharides).…”