Establishment of droplet digital PCR detection system for Helicobacter pylori virulence genes
This study aimed to establish the digital PCR system for Helicobacter pylori(Hp)virulence genes detection,pro-viding an accurate and sensitive quantitative detection method for Hp diagnosis.Specific primer and probe was designed based on the Hp vacA and cagA sequences,and quality control bacteria was used to conduct specificity testing.The gradient method was used to set the primer concentrations and annealing temperatures to optimize the reaction conditions and sys-tem.The sensitivity was detected using gradient diluted DNA as templates.The accuracy was detected using different con-centration templates with multiple repeated tests.The results showed that the designed primers and probes could specifically detect Hp vacA and cagA genes without the interference from E.coli and other bacteria.The optimal reaction temperature for vacA and cagA was 55.0℃ and 57.9℃,the optimal primer concentration was 650 nmol/L and 550 nmol/L,the linear fit-ting degree R2 was 0.999 1 and 0.999 5,and the CV values of samples with different concentrations were less than 10%,re-spectively.The Hp digital PCR detection for system vacA and cagA established in this study had the advantages of high specificity,sensitivity,and repeatability,which could provide accurate and reliable technical support for Hp pathological detec-tion and scientific research.