Helicobacter pylori eradication decreases the expression of glycosylphosphatidylinositol anchored complement regulators , decay accelerating factor and homologous restriction factor 20 … (2005 Aug)
helicobacter pylori eradication decreases the expression of glycosylphosphatidylinositol anchored complement regulators , decay accelerating factor and homologous restriction factor 20 , in human gastric epithelium . background : It has previously been reported that there is a strong correlation between the expression of glycosylphosphatidylinositol ( GPI ) anchored complement membrane inhibitor in gastric epithelium and the severity of inflammation of gastric mucosa . To investigate the regulation of complement activity in gastric epithelium during helicobacter pylori ( H . pylori ) associated gastritis , the expression of GPI anchored complement membrane inhibitors , decay accelerating factor ( DAF ) and 20 kDa homologous restriction factor 20 ( hrf20 ) , and membrane cofactor protein ( MCP ) , which is a transmembrane protein , were evaluated after removal of the H . pylori stimulus . furthermore , the expression of the complement fragment , C3c , was also investigated . methods : forty six patients with epigastric symptoms and endoscopically confirmed peptic ulcer or gastritis who had H . pylori infection of the gastric mucosa were enrolled in the present study . biopsy specimens were obtained from the gastric antrum and corpus 1 month before and after eradication . helicobacter pylori infection was determined by the rapid urease test , histology , and culture before eradication , and by histology , culture , and urea breath test after eradication . gastric biopsy specimens obtained before and after eradication were evaluated for infiltration by neutrophils and mononuclear cells . The expression …

Relationship of helicobacter pylori infection to several malignant and non malignant gastrointestinal diseases. (1998 Jan)
relationship of helicobacter pylori infection to several malignant and non malignant gastrointestinal diseases . The importance of the helicobacter pylori infection was investigated as a risk factor for several gastrointestinal diseases . In this study 203 patients with gastric cancer , 61 with peptic ulcus , 60 with gastritis and 100 asymptomatic control subjects were investigated . serum samples were examined for IgC antibodies to H . pylori by enzyme linked immunoassay tissue samples were stained for H . pylori by wartin stary technique and by giemsa for routine histopathology . H . pylori seropositivity was 58 . 1 in gastric cancer , 54 in peptic ulcus , 63 . 3 in gastritis and 27 in asymptomatic control group . there was a 10 . 1 discordance between the serum and tumor determinants in the seropositive group and 11 . 3 of discordance in the seronegative group . The frequency of H . pylori seropositivity was lowest in cardia tumors ( 22 . 7 ) and highest in antral tumors ( 65 . 5 , p 0 . 00002 ) . H . pylori seropositivity was 29 in diffuse type of histology , 35 in mixed type and 79 in the intestinal type ( p 0 . 00000 ) . In the gastric cancer patients the frequent use of salty food ( p 0 . 00001 , OR 6 . 4 ) , excessive salt , pickled food ( p 0 . 0000 , OR 24 . 92 ) and …

Expression of lewis antigens and their precursors in gastric mucosa : relationship with helicobacter pylori infection and gastric carcinogenesis. (2006 Apr)
expression of lewis antigens and their precursors in gastric mucosa : relationship with helicobacter pylori infection and gastric carcinogenesis . lewis ( Le ) associated antigens are carbohydrates that are related biochemically to the ABO blood groups , and may have a role in helicobacter pylori adherence . To evaluate their relationship to clinicopathological outcomes , gastric Le expression , including type 1 precursor , type 1 H , Le ( a ) , Le ( b ) , Le ( x ) , Le ( y ) and sialylated Le ( a ) ( CA19 9 ) , was evaluated immunohistochemically in 233 gastric biopsy specimens obtained at routine gastroscopy . expression was also investigated in gastric tissues showing chronic gastritis , intestinal metaplasia , and carcinoma from 42 patients with gastric cancer . A polymerase chain reaction was performed for H . pylori and the bacterial baba2 gene . We identified type 1 precursor expression in 34 . 3 , type 1 H in 55 . 8 , Le ( a ) in 44 . 2 , Le ( b ) in 82 . 0 , Le ( x ) in 44 . 2 , Le ( y ) 56 . 7 , and CA19 9 in 16 . 3 of the 233 gastric biopsy specimens . expression of type 1 H , Le ( b ) , and CA19 9 was significantly associated with H . pylori infection and histological features ( p 0 . 05 ) …

Interaction of helicobacter pylori ( strain 151 ) and campylobacter coli with human peripheral polymorphonuclear granulocytes. (1994 Feb)
interaction of helicobacter pylori ( strain 151 ) and campylobacter coli with human peripheral polymorphonuclear granulocytes . helicobacter pylori associated gastritis is characterized by dense mucosal inflammatory infiltrations with predominantly neutrophilic granulocytes , together with a local and systemic immune response . nevertheless , the natural course of the infection is chronic in nature , and active phagocytosis of H . pylori by mucosal granulocytes was only rarely observed . The aim of the present study was to investigate with electronmicroscopic methods the interaction of H . pylori with freshly harvested human peripheral granulocytes , with campylobacter coli as control organism . bacteria , either untreated or opsonized with complement or antiserum , were coincubated with phagocytes for up to 120 min . after defined time periods the following parameters were electronmicroscopically evaluated : i ) internalization of bacteria . , ii ) morphological characteristics of bacteria and phagocytes , iii ) decrease of lysosomes , and iv ) by use of myeloperoxidase staining , the characteristics of phagolysosomal fusion . In the absence of complement , both organisms were internalized to a comparable extent . however , in contrast to C . coli , remarkable amounts of H . pylori cells remained extracellularly attached even after 120 min of coincubation , as well as internalized bacteria remained morphologically largely unimpaired . If complement was present , internalization and morphological destruction of H . pylori cells were significantly enhanced . The latter was characterized by rounding and swelling of H …

Subcellular and functional proteomic analysis of the cellular responses induced by helicobacter pylori. (2006 Mar)
subcellular and functional proteomic analysis of the cellular responses induced by helicobacter pylori . helicobacter pylori infection is a crucial factor in the pathogenesis of several digestive disorders , including peptic ulcers , chronic gastritis , and gastric cancer . moreover H . pylori induces disease specific protein expression in gastric epithelial cells . The aim of the present study was to characterize proteins differentially expressed in H . pylori infected gastric epithelial AGS cells . An in vitro model was established using a multiplicity of infection of 100 and evaluating the effectiveness of H . pylori infection by functional analyses . changes in protein patterns were identified using a proteomic approach consisting of two dimensional fluorescence difference gel electrophoresis and mass spectrometry . The expression of many proteins was found to be altered , and 28 of these were identified and classified as protein synthesis and folding related proteins , cytoskeleton proteins , metabolic enzymes , transcription and translation related proteins , angiogenesis / metastasis related proteins , cell communication / signal transduction related proteins , or others ( oxygen regulated protein and oncoprotein ) . The expression profiles of eight of these proteins , laminin gamma 1 chain precursor , valosin containing protein , heat shock 70 kDa protein , mitochondrial matrix protein P1 , fk506 binding protein 4 , T complex protein 1 , enolase alpha , and 14 3 3 beta were further examined in cancerous and paired surrounding normal tissues by immunoblot assay and immunohistochemical …

Features of gastritis predisposing to gastric adenoma and early gastric cancer. (2002 Sep)
features of gastritis predisposing to gastric adenoma and early gastric cancer . background / AIMS : helicobacter pylori gastritis is a risk factor for the development of gastric cancer . The results of several studies indicate that gastric adenomas , which are considered premalignant lesions , may also be associated with H pylori gastritis . however , it is not clear whether there are different patterns of gastritis in these patients compared with patients with gastric cancer or patients with H pylori gastritis alone . therefore , this study was designed to investigate the patterns of gastritis in these three groups of patients . methods : The histological features of gastric mucosa at a distance from the tumour were analysed prospectively in 118 patients with gastric adenoma ( mean age , 71 . 8 ; female to male ratio , 6 : 4 ) . In addition , for every patient with H pylori associated gastric adenoma an age and sex matched control patient with either H pylori associated early gastric cancer of the intestinal type or H pylori gastritis only was investigated . results : Only 60 patients ( 50 . 9 ) with gastric adenoma were infected with H pylori . In the remaining patients , complete atrophic gastritis predominated . In those patients with adenoma and H pylori infection , the gastritis was similar to that seen in patients with early gastric cancer ( median score , 2 for activity and degree of gastritis in the antrum …

The association of helicobacter pylori with gastric cancer and preneoplastic gastric lesions in chiapas , mexico. (1993 Feb)
The association of helicobacter pylori with gastric cancer and preneoplastic gastric lesions in chiapas , mexico . background : helicobacter pylori recently was identified as a risk factor for gastric cancer . Its association with preneoplastic conditions of the stomach , however , is undocumented . methods : gastric biopsy specimens from 245 symptomatic patients were examined for neoplastic and preneoplastic lesions and for gastric H . pylori infection . The sera of 183 subjects were tested by enzyme linked immunosorbent assay ( elisa ) for anti H . pylori immunoglobulin G . results : histologic H . pylori infection , usually accompanied by acute and chronic gastritis , was found in 85 . 7 of patients . there was a strong association between H . pylori in the tissue and atrophy ( relative risk , 15 . 0 ; 95 confidence interval , 4 . 2 56 . 6 ) , intestinal metaplasia ( relative risk , 5 . 7 ; 95 confidence interval , 1 . 9 16 . 8 ) , and dysplasia or cancer ( relative risk , 4 . 0 ; 95 confidence interval , 1 . 1 14 . 8 ) . The elisa was 93 . 2 sensitive and 57 . 1 specific for histologic infection with a positive predictive value of 96 . 1 . The overall seroprevalence rate was 86 . 1 , with no significant difference in rates between patients with cancer precursors and those with normal stomachs . conclusions …

Increased thrombin generation and circulating levels of tumour necrosis factor alpha in patients with chronic helicobacter pylori positive gastritis. (2004 Jul)
increased thrombin generation and circulating levels of tumour necrosis factor alpha in patients with chronic helicobacter pylori positive gastritis . background : conflicting data have been reported concerning the relationship between helicobacter pylori infection and coronary heart disease . AIM : To evaluate clotting system activation and plasma levels of tumour necrosis factor alpha , a procoagulant cytokine , in patients with H . pylori positive and negative gastritis . methods : three groups of patients were identified : 38 with H . pylori positive gastritis , 18 with H . pylori negative gastritis , and 40 H . pylori negative controls with normal gastric mucosa . plasma levels of prothrombin fragment 1 2 ( F1 2 ) and tumour necrosis factor alpha were assayed . patients were also controlled after 2 and 6 months following standard H . pylori eradication treatment . results : At baseline , fragment 1 2 and tumour necrosis factor alpha levels in H . pylori positive patients were significantly higher than those in H . pylori negative patients with gastritis ( P 0 . 05 and P 0 . 01 , respectively ) . after H . pylori eradication , fragment 1 2 and tumour necrosis factor alpha levels showed a significant decrease at 2 months ( P 0 . 03 and P 0 . 02 , respectively ) and a further reduction at 6 months , reaching levels observed in H . pylori negative patients and controls . conclusions : The increase thrombin …

Complement activation directly induced by helicobacter pylori. (2001 Mar)
complement activation directly induced by helicobacter pylori . background AND AIMS : helicobacter pylori is a frequent gram negative colonizer of the human stomach . Its interaction with complement may be involved in the pathogenesis of chronic gastritis , and was mechanistically studied in vitro . methods : Four H . pylori strains , 2 cytotoxin associated genes ( cag ) A and 2 cagA , were isolated from infected patients . bacteria or purified H . pylori lipopolysaccharides ( LPSs ) were incubated with nonimmune serum at 37 degrees C ; the activation products C3b / iC3b / C3c ( C3bc ) and terminal complement complex ( TCC ) were then quantified by immunoassays . The serum sensitivity of 1 strain ( L01 , cagA ) was tested by counting the numbers of colony forming units . results : All strains and LPSs generated large amounts of C3bc and TCC . blocking of the classic complement pathway by the calcium chelator ethylene glycol tetraacetic acid ( EGTA ) markedly reduced the complement products , suggesting that H . pylori and its LPSs directly engage the classic activation pathway . H . pylori was shown to be serum sensitive , but 30 or more nonimmune serum was necessary to induce marked killing . after 5 minutes , swelled bacteria coated with C3bc and TCC were shown . conclusions : H . pylori is complement sensitive and activates the classic pathway even in the absence of specific antibodies . released cell …

Interactions between gastric epithelial stem cells and helicobacter pylori in the setting of chronic atrophic gastritis. (2006 Feb)
interactions between gastric epithelial stem cells and helicobacter pylori in the setting of chronic atrophic gastritis . chronic atrophic gastritis ( ChAG ) , a helicobacter pylori associated risk factor for the development of gastric cancer , involves loss of acid producing parietal cells . recent studies in gnotobiotic mouse models of ChAG have shown that parietal cell loss results in amplification of multi and oligo potential gastric stem cells that express sialylated glycan receptors recognized by H . pylori adhesins . moreover , H . pylori resides within a subset of these stem cells . studies of the transcriptomes of gastric stem cells , harvested directly from the stomachs of uninfected mice , using laser capture microdissection , suggest that they have the ability to complement some of the metabolic needs of H . pylori . these findings indicate that proliferating and non proliferating gastric stem cells provide a habitat that could support H . pylori persistence in a gastric ecosystem that has lost its acid barrier to colonization by environmental , oral and intestinal microbes . One consequence to the host might be an increased risk of tumorigenesis .

The role of decay accelerating factor as a receptor for helicobacter pylori and a mediator of gastric inflammation. (2006 May)
The role of decay accelerating factor as a receptor for helicobacter pylori and a mediator of gastric inflammation . persistent gastritis induced by helicobacter pylori is the strongest known risk factor for peptic ulcer disease and distal gastric adenocarcinoma , a process for which adherence of H . pylori to gastric epithelial cells is critical . decay accelerating factor ( DAF ) , a protein that protects epithelial cells from complement mediated lysis , also functions as a receptor for several microbial pathogens . In this study , we investigated whether H . pylori utilizes DAF as a receptor and the role of DAF within H . pylori infected gastric mucosa . In vitro studies showed that H . pylori adhered avidly to chinese hamster ovary cells expressing human DAF but not to vector controls . In H . pylori , disruption of the virulence factors vacA , cagA , and cagE did not alter adherence , but deletion of DAF complement control protein ( CCP ) domains 1 4 or the heavily O glycosylated serine threonine rich COOH terminal domain reduced binding . In cultured gastric epithelial cells , H . pylori induced transcriptional up regulation of DAF , and genetic deficiency of DAF attenuated the development of inflammation among H . pylori infected mice . these results indicate that DAF may regulate H . pylori epithelial cell interactions relevant to pathogenesis .

Lack of gastritis and of an adaptive immune response in interferon regulatory factor 1 deficient mice infected with helicobacter pylori. (2001 Feb)
Lack of gastritis and of an adaptive immune response in interferon regulatory factor 1 deficient mice infected with helicobacter pylori . To study the role of T cell responses in helicobacter pylori gastritis , c57bl / 6 wild type and interferon regulatory factor 1 deficient ( IRF 1 ( / ) ) mice were infected with the mouse adapted H . pylori sydney strain . Mice lacking the transcription factor IRF 1 are defective in Th1 development and are therefore biased to mount a Th2 type response . after 4 months of infection , c57bl / 6 mice developed severe gastritis and atrophy and mounted a Th1 type response towards H . pylori . The Th1 response was abrogated in IRF 1 ( / ) mice . This defective Th1 response was associated with the total lack of gastritis and atrophy in IRF 1 ( / ) mice despite severe colonization with H . pylori . In addition , IRF 1 ( / ) mice did also not develop a Th2 reaction , since they failed to generate H . pylori specific antibodies and to produce IL 4 in response to H . pylori antigens in vitro . Thus , the transcription factor IRF 1 is necessary for the development of gastritis and atrophy in H . pylori infected wild type mice , suggesting a role of Th1 cells in the pathogenesis of H . pylori associated diseases .

Neutrophil activation by helicobacter pylori. (1991 Oct)
neutrophil activation by helicobacter pylori . helicobacter pylori infection of the stomach is accompanied by a persistent polymorphonuclear leukocyte ( PMNL ) infiltrate of the mucosa . The aim of this work was to study the activation of human PMNL by substances produced by H pylori . filtered H pylori conditioned media stimulated a significant PMNL oxidative burst ( p less than 0 . 002 ) . This was equal to 26 of the maximal response stimulated by the PMNL chemotactic peptide N formyl methionyl leucyl phenylalanine ( FMLP , 1 mumol / l ) . The response to FMLP was prolonged by the combined presence of complement inactivated human anti H pylori plasma and conditioned medium ( p less than 0 . 002 ) . High pressure liquid chromatography of an extract of conditioned medium showed a fraction that stimulated PMNL , eluted , and antigenically cross reacted with FMLP . washed H pylori cells , and those opsonised with complement inactivated human anti H pylori plasma , did not induce a significant oxidative burst . opsonized H pylori , however , prolonged the oxidative burst induced by FMLP ( p less than 0 . 02 ) . In conclusion , H pylori synthesizes and secretes a substance , probably FMLP , that may account for the PMNL accumulation that accompanies H pylori infections . immune complexes composed of H pylori antigen and specific antibody potentiate the PMNL oxidative burst . This combination of H pylori derived products , …

Role for complement in development of helicobacter induced gastritis in interleukin 10 deficient mice. (2003 Nov)
Role for complement in development of helicobacter induced gastritis in interleukin 10 deficient mice . The mechanisms by which the immune response can eradicate gastric helicobacter infection are unknown . We hypothesized that helicobacter induced activation of the complement system could promote both inflammation and eradication of helicobacter from the stomach . In vitro studies demonstrated that helicobacter felis activates complement in normal mouse serum but not in serum from Rag2 ( / ) mice , indicating that H . felis activates complement through the classical pathway . Next , we infected complement depleted wild type control and interleukin 10 deficient ( IL 10 ( / ) ) mice with H . felis . helicobacter infection of wild type mice elicited a mild , focal gastritis and did not alter serum complement levels . infection of IL 10 ( / ) mice with H . felis elicited severe gastritis . after the initial colonization , the IL 10 ( / ) mice completely cleared helicobacter from the stomach by day 8 . In contrast to wild type mice , H . felis infected IL 10 ( / ) mice had a marked increase in serum complement levels . complement depletion of wild type mice did not affect the intensity of gastric inflammation or the extent of helicobacter colonization compared to that for the wild type control mice . In contrast , complement depletion of helicobacter infected IL 10 ( / ) mice decreased the severity of gastritis , decreased the …

Helicobacter pylori infection , garlic intake and precancerous lesions in a chinese population at low risk of gastric cancer. (1999 Apr)
helicobacter pylori infection , garlic intake and precancerous lesions in a chinese population at low risk of gastric cancer . background : cangshan county of shandong province has one of the lowest rates of gastric cancer ( GC ) in china . while intestinal metaplasia ( IM ) and dysplasia ( DYS ) are less common in cangshan than in areas of shandong at high risk of GC , these precursor lesions nevertheless affect about 20 of adults age or 55 . subjects AND setting : In order to evaluate determinants of IM and DYS in cangshan county , a low risk area of GC a survey was conducted among 214 adults who participated in a gastroscopic screening survey in cangshan county in 1994 . method : A dietary interview and measurement of serum helicobacter pylori antibodies were performed . results : The prevalence of H . pylori was lowest ( 19 ) among those with normal gastric mucosa , rising steadily to 35 for superficial gastritis ( SG ) , 56 for chronic atrophic gastritis ( CAG ) , 80 for IM , and 100 for DYS . The prevalence odds of precancerous lesions were compared with the odds of normal histology or SG . The odds ratio ( OR ) or CAG associated with H . pylori positivity was 4 . 2 ( 95 confidence interval CI : 1 . 7 10 . 0 ) , while the OR of IM / DYS associated with H . pylori …

Altered expression of membrane inhibitors of complement in human gastric epithelium during helicobacter associated gastritis. (1999 Mar)
altered expression of membrane inhibitors of complement in human gastric epithelium during helicobacter associated gastritis . AIMS : membrane inhibitors of complement are thought to protect bystander cells from complement mediated damage . expression of these proteins is enhanced in the colonic mucosa of patients with ulcerative colitis . Our aim was to investigate the regulation of complement activity in helicobacter associated chronic gastritis . methods AND results : We immunohistochemically assayed expression of three membrane inhibitors of complement , decay accelerating factor ( DAF ; CD55 ) , 20 kDa homologous restriction factor ( hrf20 ; CD59 ) and membrane cofactor protein ( MCP ; CD46 ) , in 55 biopsy specimens of the human gastric mucosa . DAF , expressed in 33 ( 60 ) of biopsy specimens , and hrf20 , expressed in 45 ( 82 ) of the samples , were located mainly on the apical surface of the epithelial cells , whereas MCP , expressed in 48 ( 87 ) of the biopsies , was found on the basolateral surface . We found strong correlation between expression of DAF on gastric mucosal epithelium and the severity of mucosal infiltration of neutrophils ( rs 0 . 875 , P 0 . 0001 ) and mononuclear cells ( rs 0 . 773 , P 0 . 0001 ) . No significant correlation was observed between hrf20 expression and neutrophil or mononuclear cell infiltration , while there was a weak negative correlation between MCP expression and these cellular …

Epithelium related deposition of activated complement in helicobacter pylori associated gastritis. (1997 Apr)
epithelium related deposition of activated complement in helicobacter pylori associated gastritis . background AND AIMS : It is unknown whether helicobacter pylori infection activates complement in vivo . mucosal deposition of various activation products of the complement system may contribute to the pathogenesis of chronic gastritis and was therefore studied by immunohistochemistry . patients AND methods : ethanol fixed antrum or body gastric tissue sections from 24 patients infected with H pylori ( determined by bacterial immunohistochemistry ) and 22 uninfected patients were examined by immunofluorescence with monoclonal antibodies to activation neoepitopes in C3b and in the terminal complex ( TCC ) . As a control group , biopsy samples from the gastric stump of 23 billroth II operated patients were studied . results : patchy , bright staining for TCC occurred below the surface epithelium and around the glands in H pylori positive and negative gastritis as well as in stump gastritis but seldom in normal mucosa . activated C3 was present at the apical face of the surface epithelium , significantly more often in the antrum and body from patients with than without H pylori infection ( p 0 . 05 and p 0 . 03 respectively ) , and particularly in samples with granulocyte infiltration ( p 0 . 04 ) . Many bacteria were coated with activated C3 towards the pit openings but seldom within the foveolae . conclusions : local complement activation was shown to take place in simple chronic gastritis , associated as well …

Cancer precursor lesions in intact stomach helicobacter pylori gastritis and in resected stomach gastritis. (2003 Oct)
cancer precursor lesions in intact stomach helicobacter pylori gastritis and in resected stomach gastritis . hemigastrectomy for benign disease and helicobacter pylori infection are risk conditions for the development of gastric cancer . Aim of the study was to compare gastric histology and precursor lesions of malignancy in these two conditions . The hemigastrectomy group included 351 consecutively endoscoped subjects operated for gastroduodenal benign disease . Six to ten biopsy specimens were routinely taken from the residual gastric mucosa . The intact stomach group included 2097 consecutively endoscoped symptomatic subjects , who did not receive eradication therapy against H . pylori . The histological findings were classified as normal mucosa ( NM ) , chronic non atrophic gastritis ( CNAG ) , chronic atrophic gastritis ( CAG ) , intestinal metaplasia ( IM ) and dysplasia ( DYS ) . One thousand and three intact stomachs were H . pylori negative , and 1094 showed H . pylori colonization . The age over fifty was a significant risk factor for the occurrence of IM ( OR 2 . 52 , P or 0 . 001 ) and DYS ( OR 3 . 46 , P or 0 . 001 ) , while Hp positivity was a risk factor for CNAG ( OR 1 . 81 , P or 0 . 001 ) and CAG ( OR 3 . 88 , P or 0 . 001 ) . gastroresection was associated to higher risk for CNAG ( OR 1 . 53 …