Marginal zone lymphomas rank as the third most prevalent form of non-Hodgkin B-cell lymphoma,trailing behind diffuse large B-cell lymphoma and follicular lymphoma.Gastric mucosa-associated lymphoid tissue lymphoma(GML...Marginal zone lymphomas rank as the third most prevalent form of non-Hodgkin B-cell lymphoma,trailing behind diffuse large B-cell lymphoma and follicular lymphoma.Gastric mucosa-associated lymphoid tissue lymphoma(GML)is a low-grade B-cell neoplasia frequently correlated with Helicobacter pylori(H.pylori)-induced chronic gastritis.On the other hand,a specific subset of individuals diagnosed with GML does not exhibit H.pylori infection.In contrast to its H.pylori-positive counterpart,it was previously believed that H.pylori-negative GML was less likely to respond to antimicrobial therapy.Despite this,surprisingly,increasing evidence supports that a considerable proportion of patients with H.pylori-negative GML show complete histopathological remission after bacterial eradication therapy.Nonetheless,the precise mechanisms underlying this treatment responsiveness are not yet fully comprehended.In recent years,there has been growing interest in investigating the role of non-H.pylori gastric helicobacters(NHPHs)in the pathogenesis of H.pylori-negative GML.However,additional research is required to establish the causal relationship between NHPHs and GML.In this minireview,we examined the current understanding and proposed prospects on the involvement of NHPHs in H.pylori-negative GML,as well as their potential response to bacterial eradication therapy.展开更多
Helicobacter heilmannii sensu lato(H.heilmannii s.l.)is a group of gastric non-Helicobacter pylori Helicobacter species that are morphologically indistinguishable from each other.H.heilmannii s.l.infect the stomach of...Helicobacter heilmannii sensu lato(H.heilmannii s.l.)is a group of gastric non-Helicobacter pylori Helicobacter species that are morphologically indistinguishable from each other.H.heilmannii s.l.infect the stomach of several animals and may have zoonotic potential.Although the prevalence of these infections in humans is low,they are associated with gastric pathology,including mucosa-associated lymphoid tissue lymphoma,making them a significant health issue.Here,the taxonomy,epidemiology,microbiology,diagnosis,and treatment of these infections will be reviewed.The gastric pathology associated with H.heilmannii s.l.infections in humans will also be addressed.Finally,the features of the complete bacterial genomes available and studies on species-specific pathogenesis will be reviewed.The understanding of the mechanisms that underlie gastric disease development mediated by the different bacterial species that constitute H.heilmannii s.l.is essential for developing strategies for prevention and treatment of these infections.展开更多
A spiral bacterium (SH9), morphologically different from Helicobacter pylori (H. pylori), was found in a 62-year-old woman’s gastric mucosa. Gastroscopic examination revealed multiple gastric ulcers near t...A spiral bacterium (SH9), morphologically different from Helicobacter pylori (H. pylori), was found in a 62-year-old woman’s gastric mucosa. Gastroscopic examination revealed multiple gastric ulcers near the pyloric ring; mapping gastric biopsy showed mild mononuclear infiltration with large lymphoid follicles in the antrum, without corpus atrophy. Urea breath test and H. pylori culture were negative, but Giemsa staining of biopsies revealed tightly coiled bacteria that immunostained with anti-H. pylori antibody. Sequencing of SH9 16S rRNA and the partial urease A and B subunit genes showed that the former sequence had highest similarity (99%; 1302/1315 bp) to Helicobacter heilmannii (H. heilmannii) sensu stricto (H. heilmannii s.s.) BC1 obtained from a bobcat, while the latter sequence confirmed highest similarity (98.3%; 1467/1493 bp) to H. heilmannii s.s. HU2 obtained from a human. The patient was diagnosed with multiple gastric ulcers associated with H. heilmannii s.s. infection. After triple therapy (amoxicillin, clarithromycin, and lansoprazole) with regimen for eradicating H. pylori, gastroscopy showed ulcer improvement and no H. heilmannii s.s. upon biopsy.展开更多
基金Scientific Initiation Scholarship Programme of the Bahia State Research Support Foundation(FAPESB),No.N°BOL1825/2022Scientific Initiation Scholarship Programme of the National Council for Scientific and Technological Development(CNPq),No.129894/2022-2CNPq Research Productivity Fellowship,No.317005/2021-9。
文摘Marginal zone lymphomas rank as the third most prevalent form of non-Hodgkin B-cell lymphoma,trailing behind diffuse large B-cell lymphoma and follicular lymphoma.Gastric mucosa-associated lymphoid tissue lymphoma(GML)is a low-grade B-cell neoplasia frequently correlated with Helicobacter pylori(H.pylori)-induced chronic gastritis.On the other hand,a specific subset of individuals diagnosed with GML does not exhibit H.pylori infection.In contrast to its H.pylori-positive counterpart,it was previously believed that H.pylori-negative GML was less likely to respond to antimicrobial therapy.Despite this,surprisingly,increasing evidence supports that a considerable proportion of patients with H.pylori-negative GML show complete histopathological remission after bacterial eradication therapy.Nonetheless,the precise mechanisms underlying this treatment responsiveness are not yet fully comprehended.In recent years,there has been growing interest in investigating the role of non-H.pylori gastric helicobacters(NHPHs)in the pathogenesis of H.pylori-negative GML.However,additional research is required to establish the causal relationship between NHPHs and GML.In this minireview,we examined the current understanding and proposed prospects on the involvement of NHPHs in H.pylori-negative GML,as well as their potential response to bacterial eradication therapy.
文摘Helicobacter heilmannii sensu lato(H.heilmannii s.l.)is a group of gastric non-Helicobacter pylori Helicobacter species that are morphologically indistinguishable from each other.H.heilmannii s.l.infect the stomach of several animals and may have zoonotic potential.Although the prevalence of these infections in humans is low,they are associated with gastric pathology,including mucosa-associated lymphoid tissue lymphoma,making them a significant health issue.Here,the taxonomy,epidemiology,microbiology,diagnosis,and treatment of these infections will be reviewed.The gastric pathology associated with H.heilmannii s.l.infections in humans will also be addressed.Finally,the features of the complete bacterial genomes available and studies on species-specific pathogenesis will be reviewed.The understanding of the mechanisms that underlie gastric disease development mediated by the different bacterial species that constitute H.heilmannii s.l.is essential for developing strategies for prevention and treatment of these infections.
基金Supported by A Grant-in-Aid for Scientific Research C-20590564 from the Ministry of Education,Culture,Sports,Science and Technology,Japan,to Ota H
文摘A spiral bacterium (SH9), morphologically different from Helicobacter pylori (H. pylori), was found in a 62-year-old woman’s gastric mucosa. Gastroscopic examination revealed multiple gastric ulcers near the pyloric ring; mapping gastric biopsy showed mild mononuclear infiltration with large lymphoid follicles in the antrum, without corpus atrophy. Urea breath test and H. pylori culture were negative, but Giemsa staining of biopsies revealed tightly coiled bacteria that immunostained with anti-H. pylori antibody. Sequencing of SH9 16S rRNA and the partial urease A and B subunit genes showed that the former sequence had highest similarity (99%; 1302/1315 bp) to Helicobacter heilmannii (H. heilmannii) sensu stricto (H. heilmannii s.s.) BC1 obtained from a bobcat, while the latter sequence confirmed highest similarity (98.3%; 1467/1493 bp) to H. heilmannii s.s. HU2 obtained from a human. The patient was diagnosed with multiple gastric ulcers associated with H. heilmannii s.s. infection. After triple therapy (amoxicillin, clarithromycin, and lansoprazole) with regimen for eradicating H. pylori, gastroscopy showed ulcer improvement and no H. heilmannii s.s. upon biopsy.
文摘目的:探讨幽门螺旋杆菌细胞毒素相关基因A(cytotoxin associated gene A,CagA)与胃黏膜中TET2(ten-eleventranslocation 2)蛋白表达的关系,以及TET2在CagA致癌过程中可能的作用。方法:Real-time PCR检测人胃黏膜上皮细胞株GES-1和胃癌细胞株MGC-803中TET2 mRNA的表达水平,细胞免疫染色法检测TET2蛋白的细胞定位及表达。将pEGFP-CagA通过脂质体介导转染GES-1细胞,用200μmol/L H2O2处理GES-1细胞建立氧化应激模型,流式细胞仪检测细胞中活性氧(reactive oxygen species,ROS)和细胞周期的变化。结果:TET2 mRNA在GES-1细胞的表达水平低于胃癌MGC-803细胞(1.00±0.08 vs 1.68±0.07,P<0.05),TET2蛋白在GES-1细胞表达水平低于胃癌MGC-803细胞(8.09±3.57 vs14.60±2.31,P<0.05)。与阴性对照组pEGFP-N1相比,pEGFP-CagA转染组GES-1细胞中TET2 mRNA表达水平升高(1.00±0.04 vs 0.06±0.00,P<0.05),TET2蛋白表达水平也升高(16.45±4.40 vs 10.82±3.39,P<0.05),ROS积累水平升高(18.39±4.52 vs 15.31±4.40,P<0.05),细胞周期检测出现明显的凋亡峰。氧化应激(H2O2处理)模型中GES-1细胞与空白对照GES-1细胞相比,TET2 mRNA水平升高(1.44±0.02 vs 1.00±0.04,P<0.05),TET2蛋白表达水平增高(15.72±4.52vs 11.74±4.34,P<0.05)。结论:幽门螺旋杆菌毒力因子CagA可诱导GES-1细胞ROS增高和细胞周期的失衡,氧化应激可以诱导TET2表达上调,TET2可能参与CagA的致癌过程。
