Objective: To investigate the association between Helicobacter pylori (Hp) virulence factor genotypes and the degree and activity of gastric mucosa pathological changes in pediatric gastroduodenal diseases. Methods: This retrospective cohort study was conducted from May 2020 to October 2020. The frozen strains of Hp, which were cultured with the gastric mucosa of 68 children with gastroscopy confirmed gastroduodenal diseases who visited the children's hospital of Zhejiang University School of Medicine from April 2012 to December 2014, were resuscitated. After extracting DNA from these Hp strains, PCR amplification and agarose gel electrophoresis were performed to determine the detection rate of cytotoxin-associated protein A (cagA),vacuolating cytotoxin A (vacA)(s1a、s1b/s2,m1/m2), outer inflammatory protein A (oipA),blood group antigen binding adhesin (babA),duodenal ulcer promoting protein A (dupA) genes; oipA genes were sequenced to determine the gene status. The patients were divided into different groups according to the findings of gastroscopy and gastric mucosa pathology. The detection rates of various virulence factor genotypes among different groups were compared using χ² tests or Fisher's exact tests. Results: The 68 Hp strains all completed genetic testing. According to the diagnostic findings of gastroscopy, the 68 cases were divided into 47 cases of superficial gastritis and 21 cases of peptic ulcer. Regarding the pathological changes of gastric mucosa, 8 cases were mild, and 60 cases were moderate and severe according to the degree of inflammation; 61 cases were active and 7 cases inactive according to the activity of inflammation. The overall detection rates of cagA, vacA, vacA s1/m2, functional oipA, babA2, and dupA virulence factor genes were 100% (68/68), 100% (68/68), 94% (64/68), 99% (67/68), 82% (56/68), and 71% (48/68), respectively. In the superficial gastritis group, their detection rates were 100% (47/47), 100% (47/47), 96% (45/47), 98% (46/47), 81% (38/47), and 70% (33/47), respectively; in the peptic ulcer group, their detection rates were 100% (21/21), 100% (21/21), 90% (19/21), 100% (21/21), 86% (18/21), and 71% (15/21), respectively. There was no statistically significant difference between the two groups (all P>0.05). In the mild gastric mucosa inflammation group, the detection rates of the above six genotypes were 8/8, 8/8, 8/8, 7/8, 7/8, and 5/8, respectively; and in the moderate to severe inflammation groups, the detection rates were 100% (60/60), 100% (60/60), 93% (56/60), 100% (60/60), 82% (49/60), and 72% (43/60), respectively, with no statistically significant difference between the two groups (all P>0.05). In the active inflammation group, the detection rate of six genotypes were 100% (61/61), 100% (61/61), 93% (57/61), 98% (60/61), 82% (50/61), and 72% (44/61), respectively; and in the inactive inflammation group, they were 7/7, 7/7, 7/7, 7/7, 6/7, and 4/7, respectively. Again, there was no statistically significant difference between the two groups (all P>0.05). There was no statistically significant difference in the detection rate of combinations of 4 or 5 virulence factor genes among the different groups (all P>0.05). Conclusions: CagA, vacA, vacA s1/m2, functional oipA, babA2, and dupA genes are not associated with superficial gastritis and peptic ulcer in children, or with the degree and activity of gastric mucosa pathological inflammation. Different gene combinations of cagA, vacA, oipA, babA2, and dupA have no significant effects on predicting the clinical outcome of Hp infection in children.
Humans ; Child ; Helicobacter pylori/genetics* ; Retrospective Studies ; Genotype ; Inflammation ; Gastritis ; Cytotoxins

Objective To explore the aptamer specific binding blood group antigen-binding adhesin (BabA) of Helicobacter pylori (H.pylori) for blocking of H.pylori adhering host cell. Methods H.pylori strain was cultured and its genome was extracted as templates to amplify the BabA gene by PCR with designed primers. The BabA gene obtained was cloned and constructed into prokaryotic expression plasmid, which was induced by isopropyl beta-D-galactoside (IPTG) and purified as target. The single stranded DNA (ssDNA) aptamers that specifically bind to BabA were screened by SELEX. Enzyme-linked oligonucleotide assay (ELONA) was used to detect and evaluate the characteristics of candidate aptamers. The blocking effect of ssDNA aptamers on H.pylori adhesion was subsequently verified by flow cytometry and colony counting at the cell level in vitro and in mouse model of infection, respectively. Meanwhile, the levels of cytokines, interleukin 6 (IL-6), IL-8, tumor necrosis factor α (TNF-α), IL-10 and IL-4 in the homogenate of mouse gastric mucosa cells were detected by ELISA. Results The genome of H.pylori ATCC 43504 strains was extracted and the recombinant plasmid pET32a-BabA was constructed. After induction and purification, the relative molecular mass (M_r) of the recombinant BabA protein was about 39 000. The amino acid sequence of recombinent protein was consistent with BabA protein by peptide mass fingerprint (PMF). Five candidate aptamers were selected to bind to the above recombinent BabA protein by SELEX. The aptamers A10, A30 and A42 identified the same site, while A3, A16 and the above three aptamers identified different sites respectively. The aptamer significantly blocked the adhesion of H.pylori in vitro. Animal model experiments showed that the aptamers can block the colonization of H.pylori in gastric mucosa by intragastric injection and reduce the inflammatory response. The levels of IL-4, IL-6, IL-8 and TNF-α in gastric mucosal homogenates in the model group with aptamer treatment were lower than that of model group without treatment. Conclusion Aptamers can reduce the colonization of H.pylori in gastric mucosa via binding BabA to block the adhesion between H.pylori and gastric mucosal epithelial cells.
Animals ; Mice ; Helicobacter pylori/genetics* ; Interleukin-4 ; Interleukin-6 ; Interleukin-8 ; Tumor Necrosis Factor-alpha ; Stomach ; Oligonucleotides ; Adhesins, Bacterial/genetics* ; Blood Group Antigens

Objective: To investigate the characteristics of duodenal bulbar microbiota in children with duodenal ulcer and Helicobacter pylori (Hp) infection. Methods: This prospective cohort study enrolled 23 children with duodenal ulcers diagnosed by gastroscopy who were admitted to the Children's Hospital of Zhejiang University School of Medicine due to abdominal pain, abdominal distension, and vomiting from January 2018 to August 2018. They were divided into Hp-positive and Hp-negative groups according to the presence or absence of Hp infection. Duodenal bulbar mucosa was sampled to detect the bacterial DNA by high-throughput sequencing. The statistical difference in α diversity and β diversity, and the relative abundance in taxonomic level between the two groups were compared. Microbial functions were predicted using the software PICRUSt. T-test, Rank sum test or χ² test were used for comparison between the two groups. Results: A total of 23 children diagnosed with duodenal ulcer were enrolled in this study, including 15 cases with Hp infection ((11.2±3.3) years of age, 11 males and 4 females) and 8 cases without Hp infection ((10.1±4.4) years of age, 6 males and 2 females). Compared with Hp-negative group, the Hp-positive group had higher Helicobacter abundance (0.551% (0.258%, 5.368%) vs. 0.143% (0.039%, 0.762%), Z=2.00, P=0.045) and lower abundance of Fusobacterium, Streptococcus and unclassified- Comamonadaceae (0.010% (0.001%, 0.031%) vs. 0.049% (0.011%, 0.310%), Z=-2.24, P=0.025; 0.031% (0.015%, 0.092%) vs. 0.118% (0.046%, 0.410%), Z=-2.10, P=0.036; 0.046% (0.036%, 0.062%) vs. 0.110% (0.045%, 0.176%), Z=-2.01, P=0.045). Linear discriminant analysis (LDA) effect sized showed that at the genus level, only Helicobacter was significantly enriched in Hp-positive group (LDA=4.89, P=0.045), while Streptococcus and Fusobacterium significantly enriched in Hp-negative group (LDA=3.28, 3.11;P=0.036,0.025, respectively). PICRUSt microbial function prediction showed that the expression of oxidative phosphorylation and disease-related pathways (pathways in cancer, renal cell carcinoma, amoebiasis, type 1 diabetes mellitus) in Hp-positive group were significantly higher than that in Hp-negative group (all P<0.05), while the expression of pathways such as energy metabolism and phosphotransferase system pathways were significantly lower than that in Hp-negative group (all P<0.05). Conclusion: In children with Hp-infected duodenal ulcers, the mucosal microbiota of the duodenal bulb is altered, characterized by an increased abundance of Helicobacter and a decreased abundance of Clostridium and Streptococcus, and possibly alters the biological function of the commensal microbiota through specific metabolic pathways.
Male ; Female ; Humans ; Child ; Duodenal Ulcer/diagnosis* ; Helicobacter Infections/complications* ; Helicobacter pylori/genetics* ; Prospective Studies ; Microbiota

Objective: To investigate the relationship between genetic polymorphisms of cytochrome P450 2C19 (CYP2C19) and the efficacy of Helicobacter pylori (Hp) eradication therapy in children. Methods: The retrospective cohort study was conducted on 125 children with gastroscopy and positive rapid urease test (RUT) from September 2016 to December 2018 who presented to the Children's Hospital of Zhejiang University School of Medicine due to gastrointestinal symptoms including nausea, vomiting, abdominal pain, bloating, acid reflux, heartburn, chest pain, vomiting blood and melena. Hp culture and drug susceptibility test were carried out with gastric antrum mucosa before treatment. All the patients completed 2 weeks of standardized Hp eradication therapy and had ¹³C urea breath test 1 month after that, which was used to evaluate the curative effect. The DNA of gastric mucosa after RUT was analyzed and CYP2C19 gene polymorphism was detected. Children were grouped according to metabolic type. Combined with the results of Hp culture and drug susceptibility, the relationship between CYP2C19 gene polymorphism and the efficacy of Hp eradicative treatment was analyzed in children. Chi square test was used for row and column variables, and Fisher exact test was used for comparison between groups. Results: One hundred and twenty five children were enrolled in the study, of whom 76 were males and 49 females. The genetic polymorphism of CYP2C19 in these children found poor metabolizer (PM) of 30.4% (38/125), intermediate metabolizer (IM) of 20.8% (26/125), normal metabolizer (NM) of 47.2% (59/125), rapid metabolizer (RM) of 1.6% (2/125), and ultrarapid metabolizer (UM) of 0. There were statistically significant in positive rate of Hp culture among these groups (χ²=124.00, P<0.001). In addition, the successful rates of Hp eradication in PM, IM, NM and RM genotypes were 84.2% (32/38), 53.8% (14/26), 67.8% (40/59), and 0, respectively, with significant differences (χ²=11.35, P=0.010); those in IM genotype was significantly lower than that in PM genotype (P=0.011). With the same standard triple Hp eradicative regimen, the successful rate of Hp eradication for IM type was 8/19, which was lower than that of PM (80.0%, 24/30) and NM type (77.3%, 34/44) (P=0.007 and 0.007, respectively). There was a significant difference in the efficacy of Hp eradication treatment among different genotypes (χ²=9.72, P=0.008). According to the clarithromycin susceptibility result, the successful rate of Hp eradication treatment for IM genotype was 4/15 in the sensitive group and 4/4 in the drug-resistant group (χ²=6.97, P=0.018). Conclusions: The genetic polymorphism of CYP2C19 in children is closely related to the efficacy of Hp eradication treatment. PM has a higher successful rate of eradication treatment than the other genotypes.
Female ; Male ; Humans ; Child ; Cytochrome P-450 CYP2C19/genetics* ; Helicobacter pylori ; Retrospective Studies ; Genotype ; Abdominal Pain

Objective To clarify whether Helicobacter pylori (H. pylori) can promote metastasis of gastric cancer cells via the high-expression of induced B cell specific Moloney murine leukemia virus integration site 1 (Bmi-1). Methods The gastric cancer tissue specimens from 82 patients were collected for this study. The protein and gene expression level of Bmi-1 in gastric adenocarcinoma tissue were detected by immunohistochemistry and real time quantitative PCR, respectively. And meanwhile the correlation between Bmi-1 levels and pathological features, and prognosis of gastric cancer were analyzed retrospectively. Then, the GES-1 cells were transfected with pLPCX-Bmi-1 plasmid and infected with H. pylori respectively. After the Bmi-1 overexpression in GES-1 cells, the invasion ability of the GES-1 cells was detected by Transwell assay, and the cell cycle and apoptosis were detected by flow cytometry. Results The mRNA and protein of Bmi-1 expression in gastric cancer tissues were higher than tumor-adjacent tissue, and the high expression of Bmi-1 was positively correlated with tumor invasion, TNM stage, tumor differentiation, lymph node metastasis and H. pylori infection. When expression of Bmi-1 was up-regulated as a result of H.pylori infection or pLPCX-Bmi-1 transfection, the GES-1 cells had higher invasiveness and lower apoptosis rate with the above treatment respectively. Conclusion H. pylori infection can inhibit the apoptosis of gastric cancer cells and promote their invasion via up-regulating expression of Bmi-1.
Humans ; Cell Line, Tumor ; Helicobacter Infections/genetics* ; Helicobacter pylori ; Lymphatic Metastasis ; Retrospective Studies ; Stomach Neoplasms/pathology* ; Polycomb Repressive Complex 1/genetics*

Helicobacter pylori (Hp) is one of most common pathogens causing gastrointestinal disorder including gastric ulcer, duodenal ulcer and gastric cancer, etc. It has been verified as class I carcinogen by WHO. Nowadays, combination antibiotics and proton pump inhibitor are mainly used to erase Hp in clinical application. However, with the increased resistance of Hp, the vaccine against Hp might become the best strategy to eradicate Hp. Elements including urease, virulence factor, outer membrane protein, flagella, play an important role in Hp infection, colonization and reproduction. They have become potential candidate antigens in the development of Hp vaccine, as reported in previous studies. Presently, these antigens-centric vaccines have been tested in animal models. Therefore, this article reviews the studies on Hp vaccine with urease, virulence genes, outer membrane protein and flagella as their candidate antigens, in an attempt to provide insights for research in this regard.
Animals ; Helicobacter pylori ; Urease/genetics* ; Helicobacter Infections/prevention & control* ; Vaccines ; Membrane Proteins

Objective To evaluate the gastric microbiome in patients with chronic superficial gastritis (CSG) and intestinal metaplasia (IM) and investigate the influence of Helicobacter pylori (H. pylori) on the gastric microbiome. Methods Gastric mucosa tissue samples were collected from 54 patients with CSG and IM, and the patients were classified into the following four groups based on the state of H. pylori infection and histology: H. pylori-negative CSG (n=24), H. pylori-positive CSG (n=14), H. pylori-negative IM (n=11), and H. pylori-positive IM (n=5). The gastric microbiome was analyzed by 16S rRNA gene sequencing. Results H. pylori strongly influenced the bacterial abundance and diversity regardless of CSG and IM. In H. pylori-positive subjects, the bacterial abundance and diversity were significantly lower than in H. pylori-negative subjects. The H. pylori-negative groups had similar bacterial composition and bacterial abundance. The H. pylori-positive groups also had similar bacterial composition but different bacterial relative abundance. The relative abundance of Neisseria, Streptococcus, Rothia, and Veillonella were richer in the I-HP group than in G-HP group, especially Neisseria (t=175.1, P<0.001). Conclusions The gastric microbial abundance and diversity are lower in H. pylori- infected patients regardless of CSG and IM. Compared to H. pylori-positive CSG group and H. pylori-positive IM, the relative abundance of Neisseria, Streptococcus, Rothia, and Veillonella is higher in H. pylori-positive patients with IM than in H. pylori-positive patients with CSG, especially Neisseria.
Gastric Mucosa/microbiology* ; Gastritis, Atrophic/microbiology* ; Gastrointestinal Microbiome/genetics* ; Helicobacter Infections/microbiology* ; Helicobacter pylori/genetics* ; Humans ; Metaplasia ; RNA, Ribosomal, 16S/genetics* ; Stomach Neoplasms

This study investigated the protective effect of total triterpenoids from Chaenomeles speciosa against Helicobacter pylori(Hp)-induced gastritis in mice and explored its possible mechanism. The chronic atrophic gastritis(CAG) model mice were randomly divided into four groups of model, total triterpenoids from C. speciosa(50 and 100 mg·kg~(-1)) and triple therapy, with C57 BL/6 J mice without Hp infection taken as the normal group. Mice in the treatment groups were given corresponding drugs once a day for 4 weeks. Then the following indexes were detected: the contents of reactive oxygen species(ROS), monocyte chemotactic protein 1(MCP-1), keratinocyte chemokines(KC), TNF-α, IL-1β, IL-6, IL-18, IL-4 and IL-10 in blood and gastric tissue, the activities and contents of LDH, MPO, SOD, GSH-Px, CAT and MDA in gastric tissue and the activities of β-glucuronidase, β-galactosidase, cathepsins B and D in blood, gastric tissue and lysosome. Besides, the mRNA expression levels of Toll-like receptor 4(TLR4), myeloid differentiation factor 88(MyD88), Bcl-2, Bcl-xl, Bax and Bad in gastric tissue were determined by quantitative real-time PCR. Western blot was employed to detect the protein expression levels of TLR4, MyD88, p-IKKβ, p-IκBα, NOD-like receptor 3(NLRP3), apoptosis-associated speck-like protein(ASC), pro-caspase-1, caspase-1, thioredoxin-interacting protein(TXNIP), pro-IL-1β, pro-IL-18, Bcl-2, Bcl-xl, Bax, Bad, cytochrome C, apoptotic protease-activating factor-1(Apaf-1), pro-caspase-9, pro-caspase-3, cleaved-caspase-9, cleaved-caspase-3, poly(ADP-ribose) polymerase 1(PARP-1), cleaved-PARP-1 and cytosol and nucleus NF-κB p65 in gastric tissue. The results indicated that the total triterpenoids from C. speciosa significantly suppressed Hp proliferation, alleviated the damage to gastric mucosa and improved lymphocyte infiltration and gland atrophy. They were also effective in reducing the activities of β-glucuronidase, β-galactosidase, cathepsins B and D in blood and gastric tissue, elevating the activities of β-glucuronidase and cathepsin D in lysosomal organelles, decreasing the contents of ROS, MCP-1, KC, TNF-α, IL-1β, IL-6, IL-18 in blood, MDA content and MPO and LDH activities in gastric tissue and increasing the contents of IL-4 and IL-10 in blood and activities of SOD, CAT and GSH-Px in gastric tissue. Other phenomena were also observed after the treatment with total triterpenoids from C. speciosa, including the down-regulation of the mRNA and protein expression levels of TLR4, MyD88, Bax and Bad, the protein expression levels of p-IKKβ, p-IκBα, NLRP3, ASC, pro-caspase-1, caspase-1, TXNIP, pro-IL-1β, pro-IL-18, cytochrome C, Apaf-1, cleaved-caspase-9, cleaved-caspase-3, cleaved-PARP-1 and nuclear NF-κB p65, reduction of p-IKKβ/IKKβ and p-IκBα/IκBα ratios and up-regulation of the mRNA and protein expression levels of Bcl-2 and Bcl-xl, up-regulation of pro-caspase-9, pro-caspace-3, cytosol NF-κB p65 protein expression levels and Bcl-2/Bax and Bcl-xl/Bad ratios in gastric tissue. These aforementioned results suggest that the total triterpenoids from C. speciosa have significant protective effects against CAG induced by Hp, and its mechanism may be related to enhancing the function of endogenous antioxidant system, suppressing the oxidative stress and inflammatory reaction induced by Hp, correcting lysosomal dysfunction and inflammatory activation of TLR4/NF-κB/NLRP3 inflammasome signaling pathway and thus inhibiting mitochondria-mediated apoptosis.
Animals ; Gastritis/drug therapy* ; Helicobacter pylori ; Mice ; NF-kappa B/genetics* ; Rosaceae ; Triterpenes

To investigate the mechanism of long non-coding RNA plasmacytoma variant translocation 1 (PVT1) in gastric cancer caused by (HP) infection. The expression of PVT1 was detected by quantitative real-time polymerase chain reaction in HP-infected normal gastric epithelial cells GES-1. Gastric cancer cell line SGC-7901 was transfected with PVT1 small interfering RNA and co-cultured with HP,and then the inflammatory cytokines such as tumor necrosis factor-α (TNF-α),interleukin (IL) -1β,IL-6 and IL-8 were detected. After PVT1 was knocked down,the effects of PVT1 on the proliferation and migration of gastric cancer cells were examined by cell scratch assay. RNA-pulldown combined with mass spectrometry was used to detect the protein binding to PVT1,and the result of mass spectrometry was verified by RNA-pulldown combined with Western blot. In HP-infected normal gastric epithelial cells GES-1,quantitative real-time polymerase chain reaction showed that PVT1 was significantly up-regulated (=7.160,=0.019). PVT1 was knocked down in gastric cancer cells,and then infected with HP. The expressions of inflammatory factors including TNF-α (=3.899,=0.011),IL-1β (=14.610,=0.000),and IL-8 (=6.557,=0.001) were significantly inhibited. Although PVT1 knockdown had no significant effect on the proliferation ability of gastric cancer cells,it inhibited the migration of cells. PVT1 might interact with RPS8 protein. PVT1 may act as a pro-inflammatory factor and regulate gastric cancer caused by HP infection.
Cell Line, Tumor ; Cell Movement ; Cytokines ; metabolism ; Epithelial Cells ; cytology ; microbiology ; Gene Knockdown Techniques ; Helicobacter Infections ; pathology ; Helicobacter pylori ; Humans ; Inflammation ; RNA, Long Noncoding ; genetics

(Hp) is widely disseminated in human, and Hp infection causes various gastrointestinal diseases, including gastric cancer. Different genotypes of Hp may cause different diseases, so the genotyping is important for clinical and basic research of Hp. This article introduces the methods for Hp genotyping, including multilocus sequence typing, pulsed-field gel electrophoresis, random amplified polymorphic DNA, amplified fragment length polymorphism, and whole-genome sequencing. By reviewing the application of these techniques in Hp genotyping and comparing their advantages and disadvantages, the article provides a theoretical basis for research into the pathogenesis, antibiotic resistance, and epidemiology of Hp infection.
Amplified Fragment Length Polymorphism Analysis ; Genotype ; Helicobacter Infections ; microbiology ; pathology ; Helicobacter pylori ; genetics ; Humans ; Polymerase Chain Reaction ; Research