西安地区幽门螺杆菌cagA, iceA基因与其所致疾病的相关性

目的: 研究幽门螺杆菌( H pylori) cagA、iceA基因及其不同组合对H pylori感染结局的影响, 探讨西安地区H pylori的优势致病基因型.方法: 用快速尿素酶试验(rapid urease test,RUT)筛选出H pylori阳性胃黏膜标本101例,细菌基因组DNA提取试剂盒提取DNA, 用聚合酶链反应(PCR)扩增尿素酶C( ureC)基因的方法筛选出H pylori阳性标本91例. 经PCR及琼脂糖凝胶电泳对cagA, iceA的基因亚型进行检测, 用χ2检验以及Fisher精确检验分析各基因及其不同组合与疾病的相关性.结果: cagA基因的阳性率为79.1%, iceA的总检出率为75.82%, 其中iceA1为50.5%, iceA2为38.5%, cagA+/ iceA1+的检出率高于其他组,单一基因及其不同组合在各疾病组中分布没有显著差异. iceA与cagA存在相关性. iceA2分别发现有229、334、439、549 bp以及229bp+334 bp的基因片段.结论: cagA+/ iceA1+是西安地区H pylori的优势致病基因型, cagA、iceA1、iceA2各单一基因以及其不同组合与感染的临床结局无关. iceA与cagA基因可能存在协同作用, 该地区iceA2基因有较大的变异性.     

幽门螺杆菌上皮接触诱导基因iceA1的克隆及序列特征

目的:克隆和分析镇江地区来源于不同疾病的(胃癌、溃疡和胃炎)幽门螺杆菌(Helicobacter pylori,H.pylori)的表皮接触诱导基因iceA1.方法:从胃十二指肠疾病患者胃黏膜组织中分离培养获得H.pylori,PCR扩增检测iceA1基因,并克隆至pMD18-T载体上,进行测序和序列分析.结果:克隆和测序了镇江地区来源于不同疾病的(胃癌、溃疡和胃炎)共12株H.pylori的i c e A1基因片段,并与标准菌株60190比对,结果显示镇江地区的H.pylori的iceA1基因中存在着3处框内缺失突变热点(780del6、809del5、914del7),这些缺失突变在溃疡和胃炎中均存在,但是胃癌株只存在809del5.对缺失片段周围的序列进行分析,这些缺失序列的两端基本都与同向重复序列相连,这可能与复制过程中滑动错配的小片段缺失模型有关.结论:iceA1序列的变异性有可能作为分析H.pylori群体遗传学的有用工具.     

幽门螺杆菌iceA基因型与胃黏膜病变的相关性

目的:研究幽门螺杆菌(H pylori)iccA基因型与胃黏膜病变的相关性.方法:用PCR方法检测552例慢性胃炎患者胃黏膜活检标本中H pylori的iceA基因在慢性炎症、活动性炎症、腺体萎缩和肠上皮化生中的存在情况.结果:在552例样本中,iceA1和iceA2亚型菌株单独检出率分别为67.2%,21.7%,iceA1和iceA2亚型均阳性的检出率7.6%,iceA1和iceA2亚型均阴性的比率3.4%.在H pylori感染的慢性炎症、活动性炎症、腺体萎缩、肠上皮化生的重度炎症iceA1的阳性率明显高于中度炎症.两者比较差异有统计学意义(83.1% vs 10.8%,85.5% vs 10.5%,75.6% vs13.0%,75.6% vs 13.0%,均,P<0.05).腺体萎缩和肠上皮化生iceA1的阳性率明显高于其他组(P<0.05).感染iceA1亚型菌株与未感染ieeA1亚型的胃黏膜病变程度差异有显著性(P<0.05).结论:iCeA1是河南地区的优势基因亚型,iceA1阳性率随炎症程度加重逐渐升高.iceA1亚型菌株与重度炎症特别是腺体萎缩和肠上皮化生关系密切.     

长春地区幽门螺杆菌耐药性与毒力基因相关性分析

目的了解长春地区幽门螺杆菌(H.pylori)耐药及毒力基因的携带情况,探究二者之间的关系。方法采用琼脂稀释法检测H.pylori对抗生素的耐药性,聚合酶链法(polymerase chain reaction,PCR)检测H.pylori cagA、vacA、iceA基因,SPSS 21.0统计软件分析毒力基因和抗菌药物耐药性的相关性。结果 69株H.pylori对CLA、MTZ、TNZ、AMX、LFX、TET和AOZ耐药率分别为52.17%(36/69)、30.43%(21/69)、47.83%(33/69)、5.80%(4/69)、37.68%(26/69)、33.33%(23/69)、30.43%(21/69)。cagA阳性检出率为89.86%(62/69);vacAs1、vacAs2、vacAm1、vacAm2、vacAi1、vacAi2、mixs1阳性检出率分别为78.26%(54/69)、21.74%(15/69)、46.38%(32/69)、53.62%(37/69)、71.01%(49/69)、28.99%(20/69)、14.49%(10/69);iceA1、iceA2、mixiceA阳性检出率分别为81.16%(56/69)、15.94%(11/69)、2.90%(2/69)。cagA、vacAs1b、vacAm1b、vacAm2、vacAi2、iceA2在耐药和敏感菌株间的分布差异无统计学意义(P0.05);vacAs1a、vacAs1c、vacAm1a、vacAi1、iceA1在耐药和敏感菌株间的分布差异有统计学意义(P0.05)。结论本地区H.pylori菌株cagA基因与抗生素耐药性无相关性,而vacA和iceA基因与抗生素的耐药性密切相关。     

幽门螺杆菌不同基因型和基因亚型与甲硝唑耐药性的研究

目的研究Helicobacter pylori菌株本身的毒力差异是否与H.pylori菌株对甲硝唑的敏感性有关。方法 用E-test方法检测109株H.pylori菌株对甲硝唑的敏感性;PCR检测H.pylori菌株不同的vacA基因亚型、cagA、iceA和babA2基因型。结果 云南地区甲硝唑耐药率为67.89％;vacA、cagA、iceAl、babA2基因的各种基因亚型和基因型在H.pylori菌株甲硝唑耐药率上无显著性差异。结论 H.pylori菌株本身的毒力差异与H.pylori菌株对甲硝唑的敏感性无关。     

Prevalence of Helicobacter pylori virulence genotypes among children in Eastern Turkey

AIM:To identify the virulence genotypes of Helicobacter pylori(H.pylori)if present in children in Eastern Turkey and if those genotypes are mostly associated with severe clinical presentations.METHODS:A total of 49 H.pylori positive Turkish children(42 with antral nodularity and 7 with peptic ulcer)who underwent upper gastrointestinal endoscopy with abdominal symptoms during the period from March 2011 to September 2012 were enrolled in this study.Antral nodularity was diagnosed endoscopically by two of the authors.We determined for the presence of cagA,vacA,cagE,iceA and babA2 genotypes of H.pylori isolates in DNA obtained directly from frozen gastric biopsy samples by polymerase chain reaction test using specific primers.RESULTS:Of the 49 H.pylori isolates studied,61.2%,91.8%,22.4%,28.6%,57.1%and 40.8%were positive for the cagA,vacA s1,cagE,iceA1,iceA2 and babA2 genes,respectively.We showed that the most common vacA subtype was s1a(79.6%).However,the s2 gene was found less frequently with an isolation rate of 8.2%of the H.pylori isolates.The genotypes iceA2 and vacA s1m2 were the most frequently found types in children with antral nodularity.In addition,the genotypes iceA1,babA2 and vacA s1m1 were found in similar ratios in all the H.pylori isolates obtained from children with peptic ulcer.The genotypes vacA s2m1and s1c were not observed in any of isolates studied.CONCLUSION:This study showed that vacA s1m2,cagA and iceA2 were the most common genotypes,and no association between antral nodularity and genotypes was observed.     

Clinical significance of Helicobacter pylori cagA and iceA genotype status

AIM:To study the presence of Helicobacter pylori(H.pylori) virulence factors and clinical outcome in H.pylori infected patients.METHODS:A prospective analysis of ninety nine H.pylori-positive patients who underwent endoscopy in our Endoscopy suite were included in this study.DNA was isolated from antral biopsy samples and the presence of cagA,iceA,and iceA2 genotypes were determined by polymerase chain reaction and a reverse hybridization technique.Screening for H.pylori infection was performed in all patie...     

Diversity of Helicobacter pylori genotypes in Iranian patients with different gastroduodenal disorders

AIM:To investigate the diversity of Helicobacter pylori(H.pylori)genotypes and correlations with disease outcomes in an Iranian population with different gastroduodenal disorders.METHODS:Isolates of H.pylori from patients with different gastroduodenal disorders were analyzed after culture and identification by phenotypic and genotypic methods.Genomic DNA was extracted with the QIAamp DNA mini kit(Qiagen,Germany).After DNA extraction,genotyping was done for cagA,vacA(s and m regions),iceA(iceA1,iceA2)and babA with specific primers for each allele using polymerase chain reaction(PCR).All patients’pathologic and clinical data and their relation with known genotypes were analyzed by using SPSS version 19.0 software.2test and Fisher’s exact test were used to assess relationships between categorical variables.The level of statistical significance was set at P<0.05.RESULTS:A total of 71 isolates from 177 patients with different gastroduodenal disorders were obtained.Based on analysis of the cagA gene(positive or negative),vacA s-region(s1or s2),vacA m-region(m1or m2),iceA allelic type(iceA1and iceA2)and babA gene(positive or negative),twenty different genotypic combinations were recognized.The prevalence of cagA,vacA s1,vacA s2,vacA m1,vacA m2,iceA1,iceA2,iceA1+iceA2and babA were 62%,78.9%,19.7%,21.1%,78.9%,15.5%,22.5%,40.8%and 95.8%,respectively.Interestingly,evaluation of PCR results for cagA in 6 patients showed simultaneous existence of cagA variants according to their size diversities that proposed mixed infection in these patients.The most prevalent genotype in cagA-positive isolates was cagA+/vacAs1m2/iceA1+A2/babA+and in cagA-negative isolates was cagA-/vacAs1m2/iceA-/babA+.There were no relationships between the studied genes and histo-pathological findings(H.pylori density,neutrophil activity,lymphoid aggregation in lamina propria and glandular atrophy).The strains which carry cagA,vacAs1/m1,iceA2and babA genes showed significant associations with severe active chronic gastritis(P=0.011,0.025,0.020 and     

淮南地区幽门螺杆菌iceA1、babA2基因分布及其细胞免疫功能研究

目的研究淮南地区幽门螺杆菌(Helicobacter pylori,H.pylori,Hp)iceA1、babA2基因分布特征及其细胞免疫功能。方法对244例有消化道症状者行胃镜检查,并在胃窦部取活检粘膜作Hp的分离培养,利用聚合酶链反应技术(PCR)测定分离培养出的Hp菌株的iceA1、babA2基因,并采用生物素-链霉亲和素(biotin-sreptavidin,BSA)系统检测患者外周血T细胞亚型,ELISA法检测其细胞因子。结果244例中,检出Hp菌株185例,其中慢性胃炎、萎缩性胃炎、胃溃疡及十二指肠球部溃疡阳性率分别为70.65%(65/92)、74.14%(43/58)、85.25%(52/61)及75.76%(25/33);基因测定结果显示,185株分离株中,79.46%(147/185)含iceA1基因,75.14%(139/185)含babA2基因;其中慢性胃炎、萎缩性胃炎、胃溃疡及十二指肠球部溃疡iceA1、babA2基因检出率分别为66.15%(43/65)、56.92%(37/65);79.07%(34/43)、74.42%(32/43);90.38%(47/52)、88.46%(46/52);92.00%(23/25)、96.00%(24/25);差异均具显著性(P<0.01)。细胞免疫功能检测,iceA1 、babA2 患者的CD 3、CD 4、CD 4/CD 8、IL-2下降,IL-6、IL-8水平升高,差异有显著性(P<0.001)。结论淮南地区Hp感染多为iceA1 、babA2 菌株,iceA1 、babA2 Hp菌株为高毒力菌株,是致消化性溃疡的重要因素;iceA1 、BabA2 菌株可使患者细胞免疫功能下降,引起患者以Th1为主的浸润反应。     

Relationship among Oxidative DNA Damage, Gastric Mucosal Density and the Relevance of cagA, vacA and iceA Genotypes of Helicobacter pylori

The aim of this study was to evaluate the relationship among oxidative DNA damage, density of Helicobacter pylori and the relevance of cagA, vacA and iceA genotypes of H. pylori. Gastric epithelial cells were isolated from 24 uninfected patients, 42 H. pylori infected patients with gastritis, and 61 patients with gastric cancer. Oxidative DNA damage was analyzed by the Comet assay, the density of H. pylori was measured by real-time polymerase chain reaction (PCR), and allelic variants of cagA, vacA and iceA were identified using the PCR. Infected patients by Helicobacter pylori cagA(+), vacAs1 m1 and iceA1 genotype showed higher levels of oxidative DNA damage than infected patients with H. pylori cagA(-), vacAs2 m2 and iceA2 genotypes and uninfected patients. Density of H. pylori did not influence oxidative DNA damage. Our results indicate that H. pylori genotype is more relevant than density for oxidative DNA damage.     

Evaluation of the clinical relevance of the iceA1 gene in patients with Helicobacter pylori infection in Japan

BACKGROUND: A novel Helicobacter pylori gene, iceA, has two allelic variants, and the iceA1 strain is associated with peptic ulcer disease. The aims of this study were to evaluate whether the possession of iceA1 gene is associated with gastric cancer or the severity of gastritis. METHODS: Ninety-seven subjects (46 patients with early gastric cancer and 51 control subjects) infected with H. pylori were studied. DNA was extracted from isolated H. pylori strains, and the presence of the iceA1 gene was examined by polymerase chain reaction. The features of gastritis were graded in accordance with the updated Sydney System, using gastric biopsy specimens. RESULTS: iceA1 was found in 61% of patients with gastric cancer and 53% of control subjects (NS). The grade of gastritis in iceA1-positive and -negative gastric mucosa was compared. Higher polymorphonuclear cell infiltration was observed in iceA1-positive subjects (P < 0.05). However, no significant difference was observed in the grades of mononuclear cell infiltration, glandular atrophy, and H. pylori density. CONCLUSIONS: Our results suggest that the iceA1 gene is not associated with the development of gastric cancer in Japan, whereas the iceA1-positive strain may induce more enhanced active gastric inflammation in cagA-positive and vacA s1/m1 strains.     

Evaluation of the Clinical Relevance of the iceA1 Gene in Patients with Helicobacter pylori Infection in Japan

Background: A novel Helicobacter pylori gene, iceA, has two allelic variants, and the iceA1 strain is associated with peptic ulcer disease. The aims of this study were to evaluate whether the possession of iceA1 gene is associated with gastric cancer or the severity of gastritis. Methods: Ninety-seven subjects (46 patients with early gastric cancer and 51 control subjects) infected with H. pylori were studied. DNA was extracted from isolated H. pylori strains, and the presence of the iceA1 gene was examined by polymerase chain reaction. The features of gastritis were graded in accordance with the updated Sydney System, using gastric biopsy specimens. Results: iceA1 was found in 61% of patients with gastric cancer and 53% of control subjects (NS). The grade of gastritis in iceA1-positive and -negative gastric mucosa was compared. Higher polymorphonuclear cell infiltration was observed in iceA1-positive subjects (P &lt; 0.05). However, no significant difference was observed in the grades of mononuclear cell infiltration, glandular atrophy, and H. pylori density. Conclusions: Our results suggest that the iceA1 gene is not associated with the development of gastric cancer in Japan, whereas the iceA1-positive strain may induce more enhanced active gastric inflammation in cagA-positive and vacA s1/m1 strains.     

Association of peptic ulcer with increased expression of Lewis antigens but not cagA, iceA, and vacA in Helicobacter pylori isolates in an Asian population

BACKGROUND: Studies in Western populations suggest that cagA, iceA, and vacA gene status in Helicobacter pylori isolates is associated with increased virulence and peptic ulcer disease. AIM: To investigate the relationship between peptic ulcer and expression of Lewis (Le) antigens as well as cagA, iceA, and vacA in H pylori isolates in Singapore. METHODS: Expression of Le antigens in H pylori isolates obtained from patients with dyspepsia was measured by enzyme linked immunosorbent assay. The cagA, iceA, and vacA status was determined by polymerase chain reaction. RESULTS: Of 108 H pylori isolates, 103 (95.4%) expressed Le(x) and/or Le(y), while Le(a) and Le(b) were expressed in 23 (21.3%) and 47 (43.5%) isolates, respectively. Expression of two or more Le antigens (Le(x), Le(y), Le(a), or Le(b)) was significantly higher in H pylori isolated from ulcer patients than in non-ulcer patients (89.6% v 73.2%, p=0.035). There were no significant differences in the prevalence of cagA or iceA1 in H pylori isolates from peptic ulcer and non-ulcer patients (86.6% v 90.2% for cagA; 70.1% v 68.3% for iceA1), and no association of peptic ulcer with any specific vacA genotype. CONCLUSIONS: The present study indicates that peptic ulcer disease is associated with increased expression of Lewis antigens but not cagA, iceA, or vacA genotype in H pylori isolates in our population. This suggests that cagA, iceA, and vacA are not universal virulence markers, and that host-pathogen interactions are important in determining clinical outcome.     

胃癌,消化性溃疡患者幽门螺杆菌和iceA基因的研究

目的研究幽门螺杆菌（Ｈｐ）的ｉｃｅＡ基因与胃癌、消化性溃疡病的关系。从１２１例患不同胃十二指肠疾病的患者胃活检组织中分离培养Ｈｐ,ＰＣＲ扩增检测Ｈｐ的ｃａｇＡ和ｉｃｅＡ基因。结果胃癌、消化性溃疡及功能性消化不良患者Ｈｐ的ｃａｇＡ基因的阳性率分别为：９１２％、８７１％和８９７％（Ｐ＞０．０５）;而ｉｃｅＡ１基因的阳性率分别为：６８０％、７１０％和６９２％（Ｐ＞０．０５）。结论我们的研究表明Ｈｐ的ｃａｇＡ和ｉｃｅＡ１基因与胃癌及消化性溃疡的发生不相关。     

Prevalence of Helicobacter pylori vacA, cagA, cagE, iceA and babA2 genotypes in Thai dyspeptic patients.

OBJECTIVES: To investigate the prevalence of the vacA, cagA, cagE, iceA, and babA2 genotypes in Helicobacter pylori strains isolated from Thai dyspeptic patients, and to determine whether any correlation exists between these genotypes and clinical manifestations. METHODS: Helicobacter pylori was examined in 112 patients (62 with non-ulcer dyspepsia (gastritis), 34 with peptic ulcer disease, and 16 with gastric cancer (GCA)), detected by culture or direct detection from gastric biopsies. Allelic variants of the vacA, cagA, cagE, iceA, and babA2 genotypes were identified by using the polymerase chain reaction. RESULTS: The positive rates for the vacAs1, vacAs2, cagA, cagE, iceA1, iceA2, and babA2 genes in H. pylori of dyspeptic patients were 100%, 0%, 98.2%, 88.4%, 45.5%, 33.1%, and 92%, respectively. The allelic variant vacAs1m1 was more prevalent (58%) than vacAs1m2 (42%). The cagA and cagE genes were commonly found together (87.5%). The most predominant genotypes were vacAs1m1, cagA, cagE, iceA1, and babA2. The various genes alone or in combination had no statistically significant association with the clinical outcomes (p>0.05). CONCLUSION: Neither single gene nor combination of vacA, cagA, cagE, iceA, and babA2 genes was significantly helpful in predicting the clinical outcome of H. pylori infection in Thai patients. The high prevalence of these genes in H. pylori isolated from Thai patient groups suggests that H. pylori strains are geographically dependent.     

上海地区幽门螺杆菌菌株iceA、babA2基因型与临床的关系

目的检测上海地区幽门螺杆菌(Hp)感染患者中Hp菌株iceA、babA2的分布特征，探讨与Hp临床感染结局相关的菌株基因型。方法141株Hp菌株分离自43例慢性胃炎(CG)、47例十二指肠球部溃疡(DU)、30例胃溃疡(GU)和21例非贲门部胃癌患者的胃镜活检标本。采用PCR方法检测Hp菌株的iceA、babA2、cagA和vacA基因型。结果141株Hp菌株中，iceA1、iceA2和babA2的总检出率分别为74．5％(105／141)、15．6％(22／141)和63．8％(90／141)，其中2例(1．4％)为iceA1、iceA2均阳性，16例(11．3％)为iceA1、iceA2均阴性。DU组的babA2检出率显著高于GU组(74．5％比50．0％。P=0．028)，DU组的cagA^ ／babA2^ 检出率亦显著高于GU组(70．2％比46．7％，P=0．039)。其余疾病组之间的babA2检出率差异无显著性。未发现不同临床疾病与iceA基因型的相关性。结论上海地区Hp感染者的菌株基因型主要是iceA1^ ／babA2^ ，babA2在DU和GU的发病机制中起不同作用。未发现iceA亚型与Hp临床感染结局有相关性。     

Prevalence of Helicobacter pylori cagA, iceA and babA2 alleles in Brazilian patients with upper gastrointestinal diseases

Helicobacter pylori is an important human pathogen associated with gastrointestinal diseases such as gastritis, gastric and duodenal ulcer (peptic ulcer disease, PUD), and gastric cancer. A number of pathogenic factors have been described for this bacterium, and some of them have been proposed as markers for the prediction of the clinical outcome. However, with the exception of the cag and vacA status, there is no universal consensus regarding the importance of the other virulence factors. Therefore, the aim of this study was to investigate the status of H. pylori strains regarding the babA and iceA alleles, as well as the cagA genotype, to reveal any association between these genotypes and clinical outcomes in Brazilian patients. The great majority (92.6%) of the strains were typed as iceA1, while 40.4% were found to possess the babA2 allele. The cagA gene was detected in 73.4% of the strains. The iceA2 and cagA genotypes were associated with PUD, while iceA1 was negatively correlated with PUD. However, considering the high percentage of strains typed as iceA1, these associations must be treated with caution. No clinical entity was associated with the babA2 allele. These results suggest that iceA1 is not a good marker for the diseases associated with H. pylori infection in Brazil. Further studies are needed in order to elucidate the relevance of the babA status, because other studies performed in Brazil have associated the babA2 allele with clinical outcomes. These results also indicate the existence of regional differences in the H. pylori genotypes and their association with clinical outcomes.