Utility of a laboratory score in the prediction of altered autonomic nervous system function in autoimmune gastritis

BACKGROUND/AIMS

Autoimmune gastritis patients may have autonomic nerve dysfunction. The goal of our study was to explore the predictive value of two scoring systems in the differentiation of altered autonomic nerve function in autoimmune gastritis patients.

MATERIALS AND METHODS

Seventy-five patients with autoimmune gastritis were evaluated by using cardiovascular reflex tests in order to delineate autonomic nerve function. Data were analyzed by using two laboratory-based scoring systems: "global score" (hemoglobin, mean corpuscular volume, gastrin, vitamin B12, and chromogranin A) and "simple score" (hemoglobin, mean corpuscular volume, gastrin) in order to discriminate deranged and normal autonomic nerve function.

RESULTS

Mean "simple" and "global" scores were significantly higher in subjects with altered autonomic dysfunction than in subjects with normal autonomic function (3.55±1.88 vs. 0.908±0.409, p<0.001 and 5.95±2.07 vs 2.46±1.28, p<0.001, respectively). Receiver operatör characteristic (ROC) analysis revealed that the optimum "simple score" cutoff point was 0.75 with a sensitivity of 86.7% and specificity of 92.3% for discriminating autoimmune gastritis patients with autonomic nerve dysfunction from patients with normal autonomic nerve function [area under the curve (AUC): 88.3, positive predictive value (PPV): 97.5% and negative predictive value (NPV): 66.6%; 95% confidence interval (CI), 88.4-99.7].

CONCLUSION

Simple score and global score have a high predictive value in the assessment of autoimmune gastritis patients with autonomic nerve dysfunction. These scoring systems may help physicians while evaluating autoimmune gastritis patients for the existence of autonomic nerve dysfunction instead of complex cardiovascular reflex tests.

Serum Biomarkers for the Diagnosis of Eosinophilic Esophagitis and Eosinophilic Gastroenteritis

Objective Clinically useful serum biomarkers for the diagnosis and monitoring of eosinophilic gastrointestinal diseases are not available. This study was conducted to examine the possible value of eosinophil-related proteins as serum biomarkers. Methods The serum concentrations of 49 cytokines, chemokines, and other proteins were measured in 29 patients with eosinophilic gastrointestinal diseases and 80 controls. Results The levels of interleukin (IL)-5, IL-33, eotaxin-3, and thymic stromal lymphopoietin (TSLP), previously reported as possible biomarkers of eosinophilic esophagitis, were not significantly elevated in the serum. In contrast, the B cell-attracting chemokine (BCA)-1/chemokine (C-X-C motif) ligand (CXCL) 13 and hemofiltrate C-C chemokine (HCC)-1/CC chemokine ligand (CCL) 14α levels were significantly elevated, while the granulocyte chemotactic protein (GCP)-2/CXCL6 levels were suppressed in patients with eosinophilic esophagitis as well as in those with eosinophilic gastroenteritis. The cutaneus T cell-attracting chemokine (CTACK)/CCL27, stromal cell-derived factor (SDF)-1/CXCL12, macrophage inflammatory protein (MIP)-3β/CCL19, and squamous cell carcinoma antigen (SCCA) 2 levels were elevated only in patients with eosinophilic esophagitis. However, there were large overlaps of data obtained from the patient and control groups, indicating that these serum biomarkers are not adequately sensitive for clinical use with presently available assay systems. Conclusion Of the 49 investigated serum proteins, none were shown to be adequately sensitive for use as biomarkers for the diagnosis or monitoring of eosinophilic gastrointestinal diseases.

Changes in Somatostatin-Like Immunoreactivity in the Sympathetic Neurons Projecting to the Prepyloric Area of the Porcine Stomach Induced by Selected Pathological Conditions

The aim of the present study was to define changes in the expression of somatostatin (SOM) in the sympathetic perikarya innervating the porcine stomach prepyloric area during acetylsalicylic-acid-induced gastritis (ASA) and experimentally induced hyperacidity (HCL) and following partial stomach resection (RES). On day 1, the stomachs were injected with neuronal retrograde tracer Fast Blue (FB). Animals in the ASA group were given acetylsalicylic acid orally for 21 days. On the 22nd day after FB injection, partial stomach resection was performed in RES animals. On day 23, HCL animals were intragastrically given 5 ml/kg of body weight of a 0.25 M aqueous solution of hydrochloric acid. On day 28, all pigs were euthanized. Then, 14-μm thick cryostat sections of the coeliac-superior mesenteric ganglion (CSMG) complexes were processed for routine double-labelling immunofluorescence. All pathological conditions studied resulted in upregulation of SOM-like (SOM-LI) immunoreactivity (from 14.97 ± 1.57% in control group to 33.72 ± 4.39% in the ASA group, to 39.02 ± 3.65% in the RES group, and to 29.63 ± 0.85% in the HCL group). The present studies showed that altered expression of SOM occurs in sympathetic neurons supplying the prepyloric area of the porcine stomach during adaptation to various pathological insults.

Anti-Inflammatory Thioredoxin Family Proteins for Medicare, Healthcare and Aging Care

Human thioredoxin (TRX) is a 12-kDa protein with redox-active dithiol in the active site -Cys-Gly-Pro-Cys-, which is induced by biological stress due to oxidative damage, metabolic dysfunction, chemicals, infection/inflammation, irradiation, or hypoxia/ischemia-reperfusion. Our research has demonstrated that exogenous TRX is effective in a wide variety of inflammatory diseases, including viral pneumonia, acute lung injury, gastric injury, and dermatitis, as well as in the prevention and amelioration of food allergies. Preclinical and clinical studies using recombinant TRX (rhTRX) are now underway. We have also identified substances that induce the expression of TRX in the body, in vegetables and other plant ingredients. Skincare products are being developed that take advantage of the anti-inflammatory and anti-allergic action of TRX. Furthermore, we are currently engaged in the highly efficient production of pure rhTRX in several plants, such as lettuce, grain and rice.

TIFA Signaling in Gastric Epithelial Cells Initiates the cag Type 4 Secretion System-Dependent Innate Immune Response to Helicobacter pylori Infection

Helicobacter pylori is a bacterial pathogen that colonizes the human stomach, causing inflammation which, in some cases, leads to gastric ulcers and cancer. The clinical outcome of infection depends on a complex interplay of bacterial, host genetic, and environmental factors. Although H. pylori is recognized by both the innate and adaptive immune systems, this rarely results in bacterial clearance. Gastric epithelial cells are the first line of defense against H. pylori and alert the immune system to bacterial presence. Cytosolic delivery of proinflammatory bacterial factors through the cag type 4 secretion system (cag-T4SS) has long been appreciated as the major mechanism by which gastric epithelial cells detect H. pylori Classically attributed to the peptidoglycan sensor NOD1, recent work has highlighted the role of NOD1-independent pathways in detecting H. pylori; however, the bacterial and host factors involved have remained unknown. Here, we show that bacterially derived heptose-1,7-bisphosphate (HBP), a metabolic precursor in lipopolysaccharide (LPS) biosynthesis, is delivered to the host cytosol through the cag-T4SS, where it activates the host tumor necrosis factor receptor-associated factor (TRAF)-interacting protein with forkhead-associated domain (TIFA)-dependent cytosolic surveillance pathway. This response, which is independent of NOD1, drives robust NF-κB-dependent inflammation within hours of infection and precedes NOD1 activation. We also found that the CagA toxin contributes to the NF-κB-driven response subsequent to TIFA and NOD1 activation. Taken together, our results indicate that the sequential activation of TIFA, NOD1, and CagA delivery drives the initial inflammatory response in gastric epithelial cells, orchestrating the subsequent recruitment of immune cells and leading to chronic gastritis.IMPORTANCEH. pylori is a globally prevalent cause of gastric and duodenal ulcers and cancer. H. pylori antibiotic resistance is rapidly increasing, and a vaccine remains elusive. The earliest immune response to H. pylori is initiated by gastric epithelial cells and sets the stage for the subsequent immunopathogenesis. This study revealed that host TIFA and H. pylori-derived HBP are critical effectors of innate immune signaling that account for much of the inflammatory response to H. pylori in gastric epithelial cells. HBP is delivered to the host cell via the cag-T4SS at a time point that precedes activation of the previously described NOD1 and CagA inflammatory pathways. Manipulation of the TIFA-driven immune response in the host and/or targeting of ADP-heptose biosynthesis enzymes in H. pylori may therefore provide novel strategies that may be therapeutically harnessed to achieve bacterial clearance.

Autoimmune gastritis: assessment of OLGA and OLGIM staging systems

BACKGROUND

Autoimmune gastritis present a risk of cancer related to atrophy and intestinal metaplasia. Two recent classifications OLGA (Operative Link on Gastritis Assessment) and OLGIM (Operative Link on Gastritic Intestinal Metaplasia assessment) have been proposed to reveal the high progressive risk forms (stages III and IV).

AIM

To evaluate the OLGA and OLGIM staging systems in chronic autoimmune gastritis.

METHODS

A descriptive single institution study of 30 cases of autoimmune gastritis. was performed over a 4-year period. The revaluation of atrophy and intestinal metaplasia, of gastric antrum and corpus, allowed to identify respectively the stages of OLGA and OLGIM systems.

RESULTS

Our autoimmune gastritis were at high-risk stages in 26,5% of cases  according to two classifications. 95% of low-risk gastritis acoording to OLGA staging presented moderete to severe corpus atrophy. A significant association was present between high-risk gastritis according to OLGA staging and neuroendocrine hyperplasia. Both OLGA and OLGIM systems showed a highly significant positive correlation between them with a mismatch at 2%.

CONCLUSIONS

The OLGA and OLGIM staging systems in autoimmune gastritis, allow probably selection of high risk forms of chronic gastritis requiring convenable care.

Upper gastrointestinal symptoms in autoimmune gastritis: A cross-sectional study

Autoimmune gastritis is often suspected for its hematologic findings, and rarely the diagnosis is made for the presence of gastrointestinal symptoms. Aims of this cross-sectional study were to assess in a large cohort of patients affected by autoimmune gastritis the occurrence and the pattern of gastrointestinal symptoms and to evaluate whether symptomatic patients are characterized by specific clinical features.Gastrointestinal symptoms of 379 consecutive autoimmune gastritis patients were systematically assessed and classified following Rome III Criteria. Association between symptoms and anemia pattern, positivity to gastric autoantibodies, Helicobacter pylori infection, and concomitant autoimmune disease were evaluated.In total, 70.2% of patients were female, median age 55 years (range 17-83). Pernicious anemia (53.6%), iron deficiency anemia (34.8%), gastric autoantibodies (68.8%), and autoimmune disorders (41.7%) were present. However, 56.7% of patients complained of gastrointestinal symptoms, 69.8% of them had exclusively upper symptoms, 15.8% only lower and 14.4% concomitant upper and lower symptoms. Dyspepsia, subtype postprandial distress syndrome was the most represented, being present in 60.2% of symptomatic patients. Univariate and multivariate analyses showed that age <55 years (OR 1.6 [CI:1-2.5]), absence of smoking habit (OR 2.2 [CI:1.2-4]), and absence of anemia (OR 3.1 [CI:1.5-6.4]) were independent factors associated to dyspepsia.Autoimmune gastritis is associated in almost 60% of cases with gastrointestinal symptoms, in particular dyspepsia. Dyspepsia is strictly related to younger age, no smoking, and absence of anemia.

CagY Is an Immune-Sensitive Regulator of the Helicobacter pylori Type IV Secretion System

BACKGROUND & AIMS

Peptic ulcer disease and gastric cancer are caused most often by Helicobacter pylori strains that harbor the cag pathogenicity island, which encodes a type IV secretion system (T4SS) that injects the CagA oncoprotein into host cells. cagY is an essential gene in the T4SS and has an unusual DNA repeat structure that predicts in-frame insertions and deletions. These cagY recombination events typically lead to a reduction in T4SS function in mouse and primate models. We examined the role of the immune response in cagY-dependent modulation of T4SS function.

METHODS

H pylori T4SS function was assessed by measuring CagA translocation and the capacity to induce interleukin (IL)8 in gastric epithelial cells. cagY recombination was determined by changes in polymerase chain reaction restriction fragment-length polymorphisms. T4SS function and cagY in H pylori from C57BL/6 mice were compared with strains recovered from Rag1-/- mice, T- and B-cell-deficient mice, mice with deletion of the interferon gamma receptor (IFNGR) or IL10, and Rag1-/- mice that received adoptive transfer of control or Ifng-/- CD4+ T cells. To assess relevance to human beings, T4SS function and cagY recombination were assessed in strains obtained sequentially from a patient after 7.4 years of infection.

RESULTS

H pylori infection of T-cell-deficient and Ifngr1-/- mice, and transfer of CD4+ T cells to Rag1-/- mice, showed that cagY-mediated loss of T4SS function requires a T-helper 1-mediated immune response. Loss of T4SS function and cagY recombination were more pronounced in Il10-/- mice, and in control mice infected with H pylori that expressed a more inflammatory form of cagY. Complementation analysis of H pylori strains isolated from a patient over time showed changes in T4SS function that were dependent on recombination in cagY.

CONCLUSIONS

Analysis of H pylori strains from mice and from a chronically infected patient showed that CagY functions as an immune-sensitive regulator of T4SS function. We propose that this is a bacterial adaptation to maximize persistent infection and transmission to a new host under conditions of a robust inflammatory response.

Russell Body Gastritis Concurrent with Eosinophilia: a case report

A 64-year-old male patient with a histological diagnosis of Russell body gastritis and with eosinophilic infiltrate in biopsy specimens is reported. The patient continued hemodialysis and pseudomembranous enteritis was contracted. Upper gastrointestinal endoscopy was performed due to poor appetite and blood eosinophilia. During endoscopy, a flare, swollen mucous membrane, and multiple verrucous erosions were noted in the gastric antrum. Biopsy and histopathological examination of gastric mucosa showed infiltration of plasma cells containing Russell bodies and eosinophils. Plasma cells containing Russell bodies were positive for CD138, immunoglobulin A (IgA) and kappa-light chain. Giemsa stained biopsy specimen revealed that the patient was negative for Helicobacter pylori. The patient was diagnosed with Russell body gastritis with eosinophilia. This is the first report of Russell body gastritis concurrent with eosinophilia. We discussed the possible correlation between the presence of plasma cells containing Russell bodies and gastric eosinophilia.

Are Mucosa CD4+/CD8+ T-Cells Expressions Correlated with the Endoscopic Appearance of Chronic Gastritis Related with Helicobacter pylori Infection?

Local inflammatory processes in the gastric mucosa are followed by extensive immune cell infiltration, resulting in chronic active gastritis characterized by a marked infiltration of T(h)1 cytokine-producing CD4+ and CD8+T-cells Objective. To investigate the correlation between CD4+/CD8+ T-cells in gastric mucosa with endoscopic appearance in chronic gastritis with or without H.pylori infection. Prospective, cross sectional study is performed in a chronic dyspepsia population in July-November 2009 at Dr. Sardjito General Hospital Yogyakarta, Indonesia. The update Sydney system was used to analyze the gastroscopy appearance. Biopsy specimens were stained with HE-stain and IHC-stain. Data were analyzed by t-test, Mann-Whitney and Spearman correlation test. Number of 88 consecutive subjects are enrolled the study (50% male; 50% female), age 46±15 years; 25% H.pylori positive. The expression of CD4+ and CD8+ were higher in H.pylori negative subjects, but only the CD4+ was significant (P=0.011). A significant correlation was found between CD4+ and CD8+ in both subjects (r(Hp+)=0.62 and r(Hp-)=0.68; P<0.05). The expression of CD4+ and CD8+ in H.pylori positive showed a significant correlation with gastric lesions (r(CD4+)=-0.60; r(CD8+)=-0.42 ; P<0.05), only erosion showed a significant difference in both subjects. A positive correlation was found between CD4+ and CD8+ infiltration in both subjects with or without H.pylori infection, and a negative correlation was only found between gastric lesion with CD4+ and CD8+ infiltration in H.pylori subject.

Local Immune Response in Helicobacter pylori Infection

There have been few studies concerning the cytokine profiles in gastric mucosa of Helicobacter pylori-infected patients with normal mucosa, chronic gastritis, and gastric carcinoma (GAC).In the present study, we aimed to elucidate the genomic expression levels and immune pathological roles of cytokines-interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-6, IL-10, transforming growth factor (TGF)-β, IL-17A, IL-32-in H pylori-infected patients with normal gastric mucosa (NGM; control), chronic active gastritis (CAG), and GAC. Genomic expression levels of these cytokines were assayed by real-time PCR analysis in gastric biopsy specimens obtained from 93 patients.We found that the genomic expression levels of IFN-γ, TNF-α, IL-6, IL-10, IL-17A mRNA were increased in the CAG group and those of TNF-α, IL-6, IL-10, IL-17A, TGF-β mRNA were increased in the GAC group with reference to H pylori-infected NGM group.This study is on the interest of cytokine profiles in gastric mucosa among individuals with normal, gastritis, or GAC. Our findings suggest that the immune response of gastric mucosa to infection of H pylori differs from patient to patient. For individual therapy, levels of genomic expression of IL-6 or other cytokines may be tracked in patients.

The Immune Battle against Helicobacter pylori Infection: NO Offense

Helicobacter pylori is a successful pathogen of the human stomach. Despite a vigorous immune response by the gastric mucosa, the bacterium survives in its ecological niche, thus favoring diseases ranging from chronic gastritis to adenocarcinoma. The current literature demonstrates that high-output of nitric oxide (NO) production by the inducible enzyme NO synthase-2 (NOS2) plays major functions in host defense against bacterial infections. However, pathogens have elaborated several strategies to counteract the deleterious effects of NO; this includes inhibition of host NO synthesis and transcriptional regulation in response to reactive nitrogen species, allowing the bacteria to face the nitrosative stress. Moreover, NO is also a critical mediator of inflammation and carcinogenesis. In this context, we review the recent findings on the expression of NOS2 in H. pylori-infected gastric tissues and epithelial cells, the role of NO in H. pylori-related diseases and H. pylori gene expression, and the mechanisms whereby H. pylori regulates NO synthesis by host cells.

Association of TLR4 and Treg in Helicobacter pylori Colonization and Inflammation in Mice

The host immune response plays an important role in the pathogenesis of Helicobacter pylori infection. The aim of this study was to clarify the immune pathogenic mechanism of Helicobacter pylori infection via TLR signaling and gastric mucosal Treg cells in mice. To discover the underlying mechanism, we selectively blocked the TLR signaling pathway and subpopulations of regulatory T cells in the gastric mucosa of mice, and examined the consequences on H. pylori infection and inflammatory response as measured by MyD88, NF-κB p65, and Foxp3 protein expression levels and the levels of Th1, Th17 and Th2 cytokines in the gastric mucosa. We determined that blocking TLR4 signaling in H. pylori infected mice decreased the numbers of Th1 and Th17 Treg cells compared to controls (P < 0.001-0.05), depressed the immune response as measured by inflammatory grade (P < 0.05), and enhanced H. pylori colonization (P < 0.05). In contrast, blocking CD25 had the opposite effects, wherein the Th1 and Th17 cell numbers were increased (P < 0.001-0.05), immune response was enhanced (P < 0.05), and H. pylori colonization was inhibited (P < 0.05) compared to the non-blocked group. In both blocked groups, the Th2 cytokine IL-4 remained unchanged, although IL-10 in the CD25 blocked group was significantly decreased (P < 0.05). Furthermore, MyD88, NF-κB p65, and Foxp3 in the non-blocked group were significantly lower than those in the TLR4 blocked group (P < 0.05), but significantly higher than those of the CD25 blocked group (P < 0.05). Together, these results suggest that there might be an interaction between TLR signaling and Treg cells that is important for limiting H. pylori colonization and suppressing the inflammatory response of infected mice.

Systems-wide analyses of mucosal immune responses to Helicobacter pylori at the interface between pathogenicity and symbiosis

Helicobacter pylori is the dominant member of the gastric microbiota in over half of the human population of which 5-15% develop gastritis or gastric malignancies. Immune responses to H. pylori are characterized by mixed T helper cell, cytotoxic T cell and NK cell responses. The presence of Tregs is essential for the control of gastritis and together with regulatory CX3CR1+ mononuclear phagocytes and immune-evasion strategies they enable life-long persistence of H. pylori. This H. pylori-induced regulatory environment might contribute to its cross-protective effect in inflammatory bowel disease and obesity. Here we review host-microbe interactions, the development of pro- and anti-inflammatory immune responses and how the latter contribute to H. pylori's role as beneficial member of the gut microbiota. Furthermore, we present the integration of existing and new data into a computational/mathematical model and its use for the investigation of immunological mechanisms underlying initiation, progression and outcomes of H. pylori infection.

EVIDENCE BASE OF LACTOBACILLUS REUTERI EFFICACY IN THE TREATMENT OF DISEASES ASSOCIATED WITH HELICOBACTER PYLORI

Helicobocterpylori (HP) - the human infection that persists for a long time in the stomach and can cause chronic gastritis, gastric and duodenal ulcer, MALT-lymphoma, gastric adenocarcinoma. There is a well-adapted niche-specific microbial community in the stomach represented by Lactobocillus, Streptococcus ahd other bacteria. Use of probiotics is considered to be an alternative or supplement to eradication therapy Among the Lactobacillus the most promising is Loctobocillus reutert who are able to have the anti-HP activity L. reureri produces powerful antimicrobial compounds such as reuterin, reuteritsin 6, reutetsiklin and metabolites that inhibit the growth of I-/P (volatile fatty acids, lactic acid, hydrogen peroxide, etc.). These compounds could reduce the adhesion of HP to gastric epithelial cells, inhibit growth HP, which leads to a significant reduction in the degree of contamination of HP and the severity of gastric mucosal inflammation. The data on the effectiveness of L. re uteri as monotherapy in patients with HP without absolute indications for eradication, and as an additional component, which increase the effectiveness of eradication are presented.

Th17 cells reflect colon submucosal pathologic changes in active eosinophilic granulomatosis with polyangiitis

BACKGROUND

Chronic eosinophilic pneumonia (CEP) or eosinophilic gastroenteritis (EG), or both, with asthma precede the onset of eosinophilic granulomatosis with polyangiitis (EGPA) in half of all EGPA patients. It is not known what determines whether patients with CEP or with EG following asthma will develop EGPA.

METHODS

We studied 17 EGPA patients and 12 patients with CEP but without EGPA. We assayed serum ICAM-1, VCAM-1, and VEGF, and the percentage of peripheral blood CD4(+) T cells producing IL-17 (Th17 cells), at both onset and remission. We also examined the numbers of submucosal eosinophils and the basement membrane-to-crypt and crypt-to-crypt distance to evaluate edema in the colon submucosa at onset and remission in EGPA and at onset in CEP.

RESULTS

Nine of 12 (75.0%) CEP patients had symptoms or endoscopic findings. Colonic submucosal eosinophil counts and edema in EGPA at onset were greater than at remission or in CEP at onset. Th17 cells (%) and serum ICAM-1 levels at onset were greater in EGPA than in CEP. In EGPA, peripheral blood Th17 cells (%) were significantly correlated with serum ICAM-1 level, colonic submucosal eosinophil count, and degree of edematous change; inversely correlated with serum VEGF level; but not correlated with VCAM-1 level.

CONCLUSIONS

Eosinophilia and colonic submucosal edematous change were greater in EGPA than in CEP. The mechanism of vasculitis in EGPA appears related to increases in serum Th17 cell numbers and ICAM-1 levels and decreases in VEGF levels.

Minimal amounts of kindlin-3 suffice for basal platelet and leukocyte functions in mice

Hematopoietic cells depend on integrin-mediated adhesion and signaling, which is induced by kindlin-3 and talin-1. To determine whether platelet and polymorphonuclear neutrophil (PMN) functions require specific thresholds of kindlin-3, we generated mouse strains expressing 50%, 10%, or 5% of normal kindlin-3 levels. We report that in contrast to kindlin-3-null mice, which die perinatally of severe bleeding and leukocyte adhesion deficiency, mice expressing as little as 5% of kindlin-3 were viable and protected from spontaneous bleeding and infections. However, platelet adhesion and aggregation were reduced in vitro and bleeding times extended. Similarly, leukocyte adhesion, extravasation, and bacterial clearance were diminished. Quantification of protein copy numbers revealed stoichiometric quantities of kindlin-3 and talin-1 in platelets and neutrophils, indicating that reduction of kindlin-3 in our mouse strains progressively impairs the cooperation with talin-1. Our findings show that very low levels of kindlin-3 enable basal platelet and neutrophil functions, whereas in stress situations such as injury and infection, platelets and neutrophils require a maximum of functional integrins that is achieved with high and stoichiometric quantities of kindlin-3 and talin-1.

Autoimmune gastritis: Pathologist’s viewpoint

Western countries are seeing a constant decline in the incidence of Helicobacter pylori-associated gastritis, coupled with a rising epidemiological and clinical impact of autoimmune gastritis. This latter gastropathy is due to autoimmune aggression targeting parietal cells through a complex interaction of auto-antibodies against the parietal cell proton pump and intrinsic factor, and sensitized T cells. Given the specific target of this aggression, autoimmune gastritis is typically restricted to the gastric corpus-fundus mucosa. In advanced cases, the oxyntic epithelia are replaced by atrophic (and metaplastic) mucosa, creating the phenotypic background in which both gastric neuroendocrine tumors and (intestinal-type) adenocarcinomas may develop. Despite improvements in our understanding of the phenotypic changes or cascades occurring in this autoimmune setting, no reliable biomarkers are available for identifying patients at higher risk of developing a gastric neoplasm. The standardization of autoimmune gastritis histology reports and classifications in diagnostic practice is a prerequisite for implementing definitive secondary prevention strategies based on multidisciplinary diagnostic approaches integrating endoscopy, serology, histology and molecular profiling.

Elucidating the function and tolerance mechanism of gamma delta (γ δ) T cells in a Helicobacter pylori infection model

In this study, the functions and mechanisms of γ δ T cells were analyzed in patients infected with Helicobacter pylori. Peripheral blood was collected from gastritis patients in the Gastroenterology Department of Ningbo No. 2 Hospital. Preliminary analyses revealed 24 H. pylori-positive and 17 H. pylori-negative patients. The wild-type and γ δ T knockout mice were infected with cultured H. pylori cells (obtained from the H. pylori-positive patients). H. pylori in mice was quantified by polymerase chain reaction; gastritis was confirmed by hematoxylin and eosin staining. The TCR-δ(-/-) mice were treated with vein adoptive immunotherapy 24 h prior to H. pylori inoculation; the same method was used to detect the extent of gastritis and bacterial colonization. The γ δ T knockout mice showed high levels of H. pylori infection than the wild-type mice; in addition, the knockout mice showed severe disease pathology. γ δ T knockout mice also displayed increased matrix metalloproteinase-9 (MMP-9) and decreased MMP-7 expression in the gastric mucosa. γ δ T cells play a protective role in patients infected with H. pylori. γ δ T cell [responsible for the production of interleukin-17 (IL-17) and IL-22] expression was increased in H. pylori-positive patients, indicating statistical significance. However, there was no significant difference in interferon-gamma + γ δ T expression between the positive and negative patients. This study demonstrated the probable involvement of γ δ T cells in the immune response of an organism, via the secretion of IL-17 and IL-22.

A pro-inflammatory role for Th22 cells in Helicobacter pylori-associated gastritis

OBJECTIVE

Helper T (Th) cell responses are critical for the pathogenesis of Helicobacter pylori-induced gastritis. Th22 cells represent a newly discovered Th cell subset, but their relevance to H. pylori-induced gastritis is unknown.

DESIGN

Flow cytometry, real-time PCR and ELISA analyses were performed to examine cell, protein and transcript levels in gastric samples from patients and mice infected with H. pylori. Gastric tissues from interleukin (IL)-22-deficient and wild-type (control) mice were also examined. Tissue inflammation was determined for pro-inflammatory cell infiltration and pro-inflammatory protein production. Gastric epithelial cells and myeloid-derived suppressor cells (MDSC) were isolated, stimulated and/or cultured for Th22 cell function assays.

RESULTS

Th22 cells accumulated in gastric mucosa of both patients and mice infected with H. pylori. Th22 cell polarisation was promoted via the production of IL-23 by dendritic cells (DC) during H. pylori infection, and resulted in increased inflammation within the gastric mucosa. This inflammation was characterised by the CXCR2-dependent influx of MDSCs, whose migration was induced via the IL-22-dependent production of CXCL2 by gastric epithelial cells. Under the influence of IL-22, MDSCs, in turn, produced pro-inflammatory proteins, such as S100A8 and S100A9, and suppressed Th1 cell responses, thereby contributing to the development of H. pylori-associated gastritis.

CONCLUSIONS

This study, therefore, identifies a novel regulatory network involving H. pylori, DCs, Th22 cells, gastric epithelial cells and MDSCs, which collectively exert a pro-inflammatory effect within the gastric microenvironment. Efforts to inhibit this Th22-dependent pathway may therefore prove a valuable strategy in the therapy of H. pylori-associated gastritis.

Multiplex-PCR-Based Screening and Computational Modeling of Virulence Factors and T-Cell Mediated Immunity in Helicobacter pylori Infections for Accurate Clinical Diagnosis

The outcome of H. pylori infection is closely related with bacteria's virulence factors and host immune response. The association between T cells and H. pylori infection has been identified, but the effects of the nine major H. pylori specific virulence factors; cagA, vacA, oipA, babA, hpaA, napA, dupA, ureA, ureB on T cell response in H. pylori infected patients have not been fully elucidated. We developed a multiplex- PCR assay to detect nine H. pylori virulence genes with in a three PCR reactions. Also, the expression levels of Th1, Th17 and Treg cell specific cytokines and transcription factors were detected by using qRT-PCR assays. Furthermore, a novel expert derived model is developed to identify set of factors and rules that can distinguish the ulcer patients from gastritis patients. Within all virulence factors that we tested, we identified a correlation between the presence of napA virulence gene and ulcer disease as a first data. Additionally, a positive correlation between the H. pylori dupA virulence factor and IFN-γ, and H. pylori babA virulence factor and IL-17 was detected in gastritis and ulcer patients respectively. By using computer-based models, clinical outcomes of a patients infected with H. pylori can be predicted by screening the patient's H. pylori vacA m1/m2, ureA and cagA status and IFN-γ (Th1), IL-17 (Th17), and FOXP3 (Treg) expression levels. Herein, we report, for the first time, the relationship between H. pylori virulence factors and host immune responses for diagnostic prediction of gastric diseases using computer-based models.

Matrix metalloproteinase 7 restrains Helicobacter pylori-induced gastric inflammation and premalignant lesions in the stomach by altering macrophage polarization

Helicobacter pylori is the strongest risk factor for the development of gastric cancer. Although the specific mechanisms by which this pathogen induces carcinogenesis have not been fully elucidated, high-expression interleukin (IL)-1β alleles are associated with increased gastric cancer risk among H. pylori-infected persons. In addition, loss of matrix metalloproteinase 7 (MMP7) increases mucosal inflammation in mouse models of epithelial injury, and we have shown that gastric inflammation is increased in H. pylori-infected MMP7(-/-) C57BL/6 mice. In this report, we define mechanisms that underpin such responses and extend these results into a genetic model of MMP7 deficiency and gastric cancer. Wild-type (WT) or MMP7(-/-) C57BL/6 mice were challenged with broth alone as an uninfected control or the H. pylori strain PMSS1. All H. pylori-challenged mice were successfully colonized. As expected, H. pylori-infected MMP7(-/-) C57BL/6 mice exhibited a significant increase in gastric inflammation compared with uninfected or infected WT C57BL/6 animals. Loss of MMP7 resulted in M1 macrophage polarization within H. pylori-infected stomachs, as assessed by Luminex technology and immunohistochemistry, and macrophages isolated from infected MMP7-deficient mice expressed significantly higher levels of the M1 macrophage marker IL-1β compared with macrophages isolated from WT mice. To extend these findings into a model of gastric cancer, hypergastrinemic WT INS-GAS or MMP7(-/-) INS-GAS mice were challenged with H. pylori strain PMSS1. Consistent with findings in the C57BL/6 model, H. pylori-infected MMP7-deficient INS-GAS mice exhibited a significant increase in gastric inflammation compared with either uninfected or infected WT INS-GAS mice. In addition, the incidence of gastric hyperplasia and dysplasia was significantly increased in H. pylori-infected MMP7(-/-) INS-GAS mice compared with infected WT INS-GAS mice, and loss of MMP7 promoted M1 macrophage polarization. These results suggest that MMP7 exerts a restrictive role on H. pylori-induced gastric injury and the development of premalignant lesions by suppressing M1 macrophage polarization.

Fulminant phlegmonitis of the esophagus, stomach, and duodenum due to Bacillus thuringiensis

We report a case of phlegmonitis of the esophagus, stomach, and duodenum in patient in an immunocompromised state. Culture of gastric juice and blood yielded Bacillus thuringiensis. This case showed that even low-virulence bacilli can cause lethal gastrointestinal phlegmonous gastritis in conditions of immunodeficiency.

Normal villous architecture with increased intraepithelial lymphocytes: a duodenal manifestation of Crohn disease

OBJECTIVES

To assess a possible association between inflammatory bowel disease (IBD) and the histologic finding in duodenal biopsy specimens of increased intraepithelial lymphocytes (IELs) with normal villous architecture.

METHODS

We identified all patients with duodenal biopsy specimens obtained between 2000 and 2010 showing increased IELs and normal architecture. Among the 74 such patients who also had IBD, we characterized the clinical features of IBD and reviewed all available upper gastrointestinal biopsy specimens.

RESULTS

Fifty-eight patients had Crohn disease, 13 had ulcerative colitis, and three had IBD, type unclassified. No duodenal sample with increased IELs had other histologic features of IBD. Among gastric biopsy specimens from 34 patients with Crohn disease, nearly half (16) had focal gastritis.

CONCLUSIONS

We propose that Crohn disease be included in the differential diagnosis for increased IELs with normal villous architecture in duodenal biopsy specimens, particularly when gastric biopsy specimens show focal gastritis.