[Serumimmunological study of moxibustion on helicobacter pylori gastritis in rats]

OBJECTIVE

To explore the immune mechanism of moxibustion on protecting gastric mucosa injury.

METHODS

Forty healthy SD rats were randomly divided into four groups: a blank group, a model group, a moxibustion acupoint group and a moxibustion non-acupoint group, 10 rats in each one. Eight days before model establishment, moxibustion at "Zusanli" (ST 36), "Zhongwan" (CV 12), "Guanyuan" (CV 4), "Pishu" (BL 20) and "Weishu" (BL 21) was applied in the moxibustion acupoint group while these acupoints' controlled points were selected in the moxibustion non-acupoint group, and no treatment was given in the model group, once a day in three groups for continuous 16 days. The helicobacter pylori (Hp) model was established by intragastric administration of Hp. HE staining microscopic examination was used to observe inflammation severity in gastric mucosa, and enzyme-linked immunosorbent assay (ELISA) was adapted to measure content of heat shock protein (HSP) 72, TNF-alpha and IL-1beta, and real-time quantitative PCR was used to measure the expression of TLR2 mRNA, TLR4 mRNA, CD14 mRNA and MyD88 mRNA in peripheral blood mononuclear cells, and western blot method was used to measure content of NFkappaB and IkappaBalpha in peripheral blood mononuclear cells.

RESULTS

Compared with the blank group, the expression of HP could be seen in the smear of gastric mucosa by Gram's staining in the model group; the inflammation severity score was obviously increased as well as content of serum HSP 72 and TNF-alpha and IL-1beta in gastric tissue; and expression of TLR2, 4 mRNA, CD14 mRNA, MyD88 mRNA, NFkappaB was increased (P < 0.01), but the expression of IkappaBalpha was reduced (P < 0.05). After the moxibustion, the inflammation severity score was reduced in the moxibustion acupoint group, and the content of serum HSP 72 was increased, and the expression of TNF-alpha and IL-1beta in gastric tissue and expression of TLR2 mRNA, TLR4 mRNA, CD14 mRNA, MyD88 mRNA and NFkappaB were reduced (P < 0.01), but the expression of IkappaBalpha was increased (P < 0.05). The differences between the moxibustion non-acupoint group and the model group were not significant (P > 0.05).

CONCLUSION

The pretreatment of moxibustion at acupoints could induce the over expression of serum HSP 72. By combining TLR 2 and 4 receptors to trigger receptor signal transduction pathways, the releases of downstream signal substances are regulated; as a result, the releases of related immune substances are regulated to relieve the gastric mucosa injury of rats with HP gastritis.

Macrophages promote progression of spasmolytic polypeptide-expressing metaplasia after acute loss of parietal cells

BACKGROUND & AIMS

Loss of parietal cells causes the development of spasmolytic polypeptide-expressing metaplasia (SPEM) through transdifferentiation of chief cells. In the presence of inflammation, SPEM can advance into a more proliferative metaplasia with increased expression of intestine-specific transcripts. We used L635 to induce acute SPEM with inflammation in mice and investigated the roles of inflammatory cells in the development of SPEM.

METHODS

To study the adaptive immune system, Rag1 knockout, interferon-γ-deficient, and wild-type (control) mice received L635 for 3 days. To study the innate immune system, macrophages were depleted by intraperitoneal injection of clodronate liposomes 2 days before and throughout L635 administration. Neutrophils were depleted by intraperitoneal injection of an antibody against Ly6G 2 days before and throughout L635 administration. Pathology and immunohistochemical analyses were used to determine depletion efficiency, metaplasia, and proliferation. To characterize SPEM in each model, gastric tissues were collected and levels of Cftr, Dmbt1, and Gpx2 mRNAs were measured. Markers of macrophage polarization were used to identify subpopulations of macrophages recruited to the gastric mucosa.

RESULTS

Administration of L635 to Rag1 knockout, interferon-γ-deficient, and neutrophil-depleted mice led to development of proliferative SPEM and up-regulation of intestine-specific transcripts in SPEM cells, similar to controls. However, macrophage-depleted mice given L635 showed significant reductions in numbers of SPEM cells, SPEM cell proliferation, and expression of intestine-specific transcripts, compared with control mice given L635. In mice given L635, as well as patients with intestinal metaplasia, M2 macrophages were the primary inflammatory component.

CONCLUSIONS

Results from studies of mouse models and human metaplastic tissues indicate that M2 macrophages promote the advancement of SPEM in the presence of inflammation.

Immune responses to Helicobacter pylori infection

Helicobacter pylori (H. pylori) infection is one of the most common infections in human beings worldwide. H. pylori express lipopolysaccharides and flagellin that do not activate efficiently Toll-like receptors and express dedicated effectors, such as γ-glutamyl transpeptidase, vacuolating cytotoxin (vacA), arginase, that actively induce tolerogenic signals. In this perspective, H. pylori can be considered as a commensal bacteria belonging to the stomach microbiota. However, when present in the stomach, H. pylori reduce the overall diversity of the gastric microbiota and promote gastric inflammation by inducing Nod1-dependent pro-inflammatory program and by activating neutrophils through the production of a neutrophil activating protein. The maintenance of a chronic inflammation in the gastric mucosa and the direct action of virulence factors (vacA and cytotoxin-associated gene A) confer pro-carcinogenic activities to H. pylori. Hence, H. pylori cannot be considered as symbiotic bacteria but rather as part of the pathobiont. The development of a H. pylori vaccine will bring health benefits for individuals infected with antibiotic resistant H. pylori strains and population of underdeveloped countries.

Inflammation-related factors predicting prognosis of gastric cancer

Gastric cancer (GC), which is mainly induced by Helicobacter pylori (H. pylori) infection, is one of the leading causes of cancer-related death in the developing world. Active inflammation initiated by H. pylori infection and maintained by inherent immune disorders promotes carcinogenesis and postoperative recurrence. However, the presence with H. pylori in tumors has been linked to a better prognosis, possibly due to the induction of antitumor immunity. Tumor infiltrations of tumor-associated macrophages, myeloid-derived suppressor cells, neutrophils, Foxp3⁺ regulatory T cells are correlated with poor prognosis. Tumor infiltrating CD8⁺ cytotoxic T lymphocytes, dendritic cells, and CD45RO T cells are generally associated with good prognosis of GC, although some subsets of these immune cells have inverse prognosis prediction values. High ratios of Foxp3⁺/CD4⁺ and Foxp3⁺/CD8⁺ in tumors are associated with a poor prognosis; whereas high Th1/Th2 ratio in tumors predicts a good prognosis. High levels of interleukin (IL)-6, IL-10, IL-32, and chemokine C-C motif ligands (CCL)7 and CCL21 in circulation, high expression of CXC chemokine receptor 4, chemokine C-C motif receptor (CCR)3, CCR4, CCR5, CCR7, hypoxia-inducible factor-1α, signal transducer activator of transcription-3, cyclooxygenase-2, and orphan nuclear receptor 4A2 in tumors are associated with an unfavorable prognosis. Increased serum levels of matrix metalloproteinases (MMP)-3, MMP-7, and MMP-11 and increased levels of MMP-9, MMP-12, and MMP-21 in tumors are consistently associated with poor survival of GC. Further emphasis should be put on the integration of these biomarkers and validation in large cohorts for personalized prediction of GC postoperative prognosis.

Impairment of ghrelin synthesis in Helicobacter pylori-colonized stomach: New clues for the pathogenesis of H. pylori-related gastric inflammation

Ghrelin, the ligand of growth hormone secretagogue receptor 1a, takes part in several functions of the digestive system, including regulation of appetite, energy homeostasis, gastric acid secretion and motility. Ghrelin has also immunoregulatory properties and is supposed to inhibit some inflammatory pathways that can mediate gastric damage. Interestingly, ghrelin synthesis is reduced in the gastric mucosa of patients with Helicobacter pylori (H. pylori) infection, a worldwide condition inducing a T helper (Th)1/Th17 cell response-driven gastritis, which may evolve towards gastric atrophy and cancer. In this article, we review the available data on the expression of ghrelin in H. pylori infection and discuss how the defective ghrelin synthesis may contribute to sustain the ongoing inflammatory response in this disease.

Helicobacter pylori gamma-glutamyl transpeptidase and its pathogenic role

Helicobacter pylori (H. pylori) gamma-glutamyl transpeptidase (GGT) is a bacterial virulence factor that converts glutamine into glutamate and ammonia, and converts glutathione into glutamate and cysteinylglycine. H. pylori GGT causes glutamine and glutathione consumption in the host cells, ammonia production and reactive oxygen species generation. These products induce cell-cycle arrest, apoptosis, and necrosis in gastric epithelial cells. H. pylori GGT may also inhibit apoptosis and induce gastric epithelial cell proliferation through the induction of cyclooxygenase-2, epidermal growth factor-related peptides, inducible nitric oxide synthase and interleukin-8. H. pylori GGT induces immune tolerance through the inhibition of T cell-mediated immunity and dendritic cell differentiation. The effect of GGT on H. pylori colonization and gastric persistence are also discussed.

[The clinical significance of evaluation of the inflammatory infiltrate in chronic gastroduodenitis in children]

OBJECTIVE

To establish the diagnostic value of the determination of leukocyte composition of inflammatory infiltrate in chronic gastroduodenite in childhood.

PATIENTS AND METHODS

We examined 103 patients aged 8-17 with chronic gastroduodenitis associated with Helicobacter pylori. To detect Hp and Epstein-Barr viral infections we used esophagogastroduodenoscopy, quick urease test, bacterioscopy of gastrobiopsies. We performed the analysis of the cellular composition of the inflammatory infiltrate.

RESULTS

It was found that the number of lymphocytes and neutrophils located in the lamina and intraepithelial increases, which is associated with the degree of inflammation. Increased to the maximum was the number of intraepithelial lymphocytes, both in the body, and in the antrum. Intensity of leukocyte infiltration is directly correlated with the increased prevalence of inflammation. Persistence of Epstein-Barr virus (35.9% of patients) is followed by more severe intraepithelial lymphocytic infiltration in the stomach. In 4-6 months after treatment 18 patients with severe gastritis were repeatedly studied for the inflammatory infiltrate. A significant decrease in the number of intraepithelial neutrophils was found.

CONCLUSION

Cellular composition of the infiltrate is an objective characteristic of chronic inflammation in the gastric mucosa. Persistence of Epstein-Barr virus is accompanied by an increase in the amount of intraepithelial lymphocytes and neutrophils.

[Mucosal immune response to Helicobacter pylori in children with gastroduodenal diseases and allergy]

In children with chronic gastritis/gastroduodenitis, erosions and ulcer of stomach and duodenum and associated allergic diseases (asthma, allergic rhinitis, atopic dermatitis) CagA, sIgA and IgE antibodies to the H. pylori were determined by ELISA in the supernatants of feces. H. pylori infection was determined according to "Maastricht IV". The frequency and contents of CagA did not differ among the groups we studied. However, in children with positive urease test the contents of CagA was significantly higher (p = 0.03) compared with other children. The highest levels of sIgA were found in the feces supernatants from non-allergic children with CG/CGD and were associated with H. pylori infection. The immune response in children with erosions and ulcer of stomach and duodenum and in children with allergy was presented the sIgE to H. pylori. Also, the negative correlation between the level sIgE to H. pylori and content sIgA was found in children with allergy. Thus, increased IgE indicates not only allergy, but also acts as a protective role in the development of anti-infective immunity.

[Cycloferon therapy of chronic gastroduodenitis in children]

The efficiency of immunomodulating therapy with cycloferon in children aged from 10 to 16 years with verified chronic gastroduodenitis was estimated. It was shown that the cycloferon treatment provided reliable increase of T- and B-cellular populations in mucous membranes of the stomach and duodenum, normalization of the number of CD8-lymphocytes, higher titers of IgG antibodies to herpes viruses 1 and 2. It also promoted reduction of inflammation in the mucous membranes along with reduction of the disease clinical signs.

A novel diabetic murine model of Candida albicans-induced mucosal inflammation and proliferation

Chronic hyperplastic candidiasis (CHC) lesions will progress to dysplasia with some of these developing squamous cell carcinoma (SCC). It is well known that diabetic patients are predisposed to candidiasis. Previously, we found that alloxan-induced diabetic rats spontaneously have mucosal hyperplasia with C. albicans infection and that those lesions progress to SCC. Here, we developed a rat model of candidiasis with diabetes progressing to mucosal proliferation. Diabetes was induced in thirty rats by single intravenous administration of alloxan. Ten nondiabetic rats and fifteen diabetic rats then received C. albicans containing solution orally, and additional fifteen diabetic rats received saline in the same manner. The administration of C. albicans induced mucosal candidiasis and the related mucosal hyperplastic changes in all the diabetic rats and progressed to SCC in one rat. Chronic suppurative inflammation of the mucosa developed in the forestomach with infection by C. albicans. The same lesions were only detected in the forestomach of 4 diabetic rats without C. albicans treatment. After C. albicans treatment, none of the nondiabetic rats showed mucosal changes or fungus infection in the forestomach. These findings demonstrate that a prolonged diabetic condition can cause C. albicans infection and enhance C. albicans-related mucosal hyperplasia.

Role of Tumor Necrosis Factor-Alpha and Interferon-Gamma inHelicobacter pyloriInfection

Immune responses to Helicobacter pylori infection play important roles in gastroduodenal diseases. The contributions of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) to the induction of gastric inflammation and to the protection from H. pylori infection were investigated using TNF-alpha geneknockout (TNF-alpha(-/-)) mice and IFN-gamma gene-knockout (IFN-gamma(-/-)) mice. We first examined the colonizing ability of H. pylori strain CPY2052 in the stomach of C57BL/6 wild-type and knockout mice. The number of H. pylori colonized in the stomach of IFN-gamma(-/-) and TNF-alpha(-/-) mice was higher than that of wild-type mice. These findings suggest that TNF-alpha and IFN-gamma may play a protective role in H. pylori infection. Furthermore, we examined the contribution of TNF-alpha and IFN-gamma to gastric inflammation. The CPY2052-infected TNF-alpha(-/-) mice showed a moderate infiltration of mononuclear cells in the lamina propria and erosions in the gastric epithelium as did wild-type mice, whereas the CPY2052-infected IFN-gamma(-/-) mice showed no inflammatory findings even 6 months after infection. These results demonstrate that IFN-gamma may play an important role in gastric inflammation induced by H. pylori infection, whereas TNF-alpha may not participate in the development of inflammatory response.

[The thyrogastric syndrome: its effects on micronutriments and gastric tumorigenesis]

The thyrogastric autoimmune syndrome (TAS) was described in patients in whom the serum cross-reacted both with gastric parietal cells antigens and thyroid antigens. We report two cases illustrating the spectrum of pathogical features of TAS. The first case associates Hashimoto's thyroiditis and anemia perniciosa,and develops a gastric neuroendocrine tumor during follow up. The second case presents with a Graves' disease and an autoimmune reversible gastritis, secondary to Helicobacter pylori. Whereas type III autoimmune polyendocrinopathy is rare, TAS is frequent in our experience. Some 13% (32/240) of patients that we have prospectively followed affected with thyroiditis have also autoimmune gastritis. Helicobacter pylori is clearly implicated in 16% of autoimmune gastritis cases. Infection, malabsorption and gastritis are potentially reversible after bacterial eradication treatment. In the other 84% of gastritis patients, no histological or serological proof of Helicobacter pylori is found. Gastric autoimmunity is then irreversible, leading to gastric severe atrophy, hypochlorhydria and hypergastrinemia. Hypergastrinemia stimulates enterochromaffin cell hyperplasia, possibly progressing to neuroendocrine tumors. We propose a diagnostic approach to improve the characterization of TAS. We review the literature on the subject and discuss some interesting animal models of infectious gastric autoimmunity.

Neonatal eosinophilic gastroenteritis: possible in utero sensitization to cow's milk protein

Rectal bleeding in neonates is an alarming sign that suggests a possible serious underlying condition, such as infection or bleeding disorder that would necessitate hospitalization and prompt intervention. We report a case of eosinophilic gastroenteritis caused by cow's milk protein allergy in a one-day- old infant, who presented with frankly bloody stools associated with massive gastrointestinal and peripheral blood eosinophilia prior to initiation of enteral feedings. The patient's outcome was favorable, with complete spontaneous recovery in one week, after a period of bowel rest, parenteral nutrition, and use of amino acid formula. The eosinophilia was also transient and gradually resolving by two months of age. Rectal bleeding secondary to allergic colitis caused by cow's milk sensitization may occur in neonates, and failure to appreciate this possibility may lead to inappropriate diagnostic or therapeutic intervention.

Autoimmune gastro-pancreatitis with anti-protein disulfide isomerase-associated 2 autoantibody in Aire-deficient BALB/cAnN mice

Although the autoimmune regulator (Aire) knockout (KO) mouse model has been reported to present various organ-specific autoimmune diseases depending on genetic background, autoimmune pancreatitis in mice of BALB/c background has not yet been reported. Here, we report that Aire KO mice with BALB/cAnN background showed significant lymphoid cell infiltration in the pancreas and stomach. To examine whether the phenotype in the pancreas and stomach is due to autoimmune reaction associated with autoantibody production, indirect immunofluorescence staining followed by Western blot analysis was performed. Consequently, the autoantibody against pancreas and stomach was detected in the sera of Aire KO mice, and the target antigen of the autoantibody was identified as protein disulfide isomerase-associated 2 (Pdia2), which was reported to be expressed preferentially in the pancreas and stomach. Thus, Aire KO mice of BALB/cAnN background can serve as a useful animal model for autoimmune gastro-pancreatitis with anti-Pdia2 autoantibody production.

Effects of radix curcumae-derived diterpenoid C on Helicobacter pylori-induced inflammation and nuclear factor kappa B signal pathways

AIM: To study effect of diterpenoid C extracted from radix curcumae on Helicobacter pylori (H. pylori)-infected inflammation, intestinal metaplasia, and nuclear factor kappa B (NF-κB) signaling pathway in vitro.

METHODS: We used I-type H. pylori to infect human gastric epithelial gastric epithelium cell line (GES-1) cell lines, and then H. pylori-infected GES-1 cells were treated with radix curcumae (RC)-derived diterpenoid C of different concentrations (5, 10, 20 μg/mL) and amoxicillin. The expression of p65, IκB kinase (IKK) α and IKKγ proteins was detected with Western blotting, and the expression of interleukin (IL)-8, IL-6 and IL-4 was determined with enzyme-linked immunosorbent assay method. Data were analyzed using SPSS software ver18.0. For comparisons between groups of more than two unpaired values, one-way analysis of variance (ANOVA) was used. If an ANOVA F value was significant, post hoc comparisons were performed between groups. If results were not normally distributed, the Mann-Whitney U test was used to compare two groups of unpaired values, whereas for comparisons between groups of more than two unpaired values, the Kruskal-Wallis H test was used. Statistical significance was established at P < 0.05.

RESULTS: The MTT assay results revealed the inhibited rate of GES-1, and indicated that the IC5 of RC-derived diterpenoid C and amoxicillin all were 5 μg/mL for gastric GES-1 cells. The expression of IL-8 was significantly increased, especially at 12 h time point; and the expression of IL-4 was decreased in H. pylori-infected GES-1 cells. After H. pylori-infected GES-1 cells were treated with RC-derived diterpenoid C of different concentrations and amoxicillin, the expression of IL-8 was decreased at 12, 24, 48, 72 h points (P < 0.01), especially in high-concentration diterpenoid C (20 μg/mL) group; and the expression of IL-4 was increased, especially in moderate and high-concentration diterpenoid C (10 and 20 μg/mL) groups. RC-derived diterpenoid C had the inhibitory effects on H. pylori-induced p65 translocation from cytoplasm into cell nucleus, H. pylori-stimulant IkBα degradation, the phosphorylation of p65 and IkBα, and the expression of IKKα and IKKβ proteins.

CONCLUSION: RC-derived diterpenoid C can block NF-κB signal pathway, effectively reducing the secretion of H. pylori-induced proinflammatory cytokine and increasing the secretion of anti-inflammatory cytokine.

[Serological assessment of Helicobacter pylori-specific antibodies and their association with gastric lesions in a high-risk population]

OBJECTIVE

To determine the distributions of six Helicobacter pylori (Hp)-specific antibodies in a high-risk population of gastric cancer (GC) and explore the relationship between Hp virulence factors and precancerous gastric lesions.

METHODS

Based on the two intervention trials conducted in Linqu County, the seropositivities for CagA, VacA, GroEL, UreA, HcpC and GGT were assessed by recombinant immunoassay (recomLine) in 623 participants with H. pylori infection determined by (13)C-urea breath test ((13)C-UBT) and/or enzyme linked immunosorbent assay (ELISA).

RESULTS

In a total of 623 participants were detected by recomLine analysis, of which 594 were Hp-positive. The seropositivities rates of CagA, VacA, GroEL, UreA, HcpC and GGT were 84.0%, 38.2%, 66.7%, 17.7%, 58.8% and 42.8%, respectively. A total of 523 participants were determined as type I infection of Hp, accounting for 88.1%. Compared with superficial gastritis (SG), the infection rate of Hp type I was higher in the chronic atrophic gastritis (CAG) (P = 0.001).

CONCLUSIONS

The results of this population-based study suggest that the virulence factors of Hp may be related to the development of GC in a Chinese high-risk population. The recomLine analysis may serve as a tool for identification of Hp strains and prediction of high-risk population of GC.

[Detection of the markers of herpesvirus infections in stomach diseases of inhabitants of the Republic of Mordovia]

The study included 120 patients with pre-cancer conditions of the stomach and 30 patients with gastric cancer stage II-IV. The ELISA method in the blood serum was used to determine the markers of the infection caused by Herpes simplex virus (HSV) types 1 and 2, Cytomegalovirus (CMV), and Epstein-Barr virus (EBV). The majority of the patients exhibited high titers of markers of Herpesvirus mixed infection. These data allow recommending the determination of IgG antibodies to antigens of herpesviruses in patients with the diseases of the stomach and assigning the appropriate antiviral drugs.

Dipterocarpus tuberculatus ethanol extract strongly suppresses in vitro macrophage-mediated inflammatory responses and in vivo acute gastritis

ETHNOPHARMACOLOGICAL RELEVANCE

Dipterocarpus tuberculatus Roxb. (Dipterocarpaceae) has been traditionally used to treat various inflammatory symptoms. However, no mechanistic studies on the anti-inflammatory actions of D. tuberculatus have been reported. This study is therefore aimed at exploring the anti-inflammatory effects of 95% ethanol extracts (Dt-EE) of this plant.

MATERIALS AND METHODS

The regulatory activity of Dt-EE and its molecular mechanism on the release of nitric oxide (NO) and prostaglandin (PG)E2 in lipopolysaccharide (LPS)-treated macrophage-like RAW264.7 cells were elucidated by evaluating the activation of transcription factors and their upstream signals and by analyzing the kinase activities of target enzymes. Furthermore, to confirm its availability for oral use, an EtOH/HCl-induced acute gastritis model was tested with this extract.

RESULTS

Dt-EE effectively suppressed LPS-mediated inflammatory responses such as the production of NO and PGE2 from macrophages in a dose-dependent manner. In particular, Dt-EE clearly blocked the activation of NF-κB by blocking the phosphorylation of its upstream enzymes IKK and Akt. Using a direct enzyme assay, Dt-EE was shown to block the enzyme activity of PDK1. Finally, this extract also remarkably ameliorated inflammatory lesions in the stomach induced by EtOH/HCl.

CONCLUSION

Our data strongly suggest that Dt-EE can be considered as a novel anti-inflammatory remedy with PDK1/NF-κB inhibitory properties and can also be used to treat gastritis symptoms. In addition, our findings can serve as a basis for further phytochemical and pharmacological studies in the future.

Caveolin-1 protects B6129 mice against Helicobacter pylori gastritis

Caveolin-1 (Cav1) is a scaffold protein and pathogen receptor in the mucosa of the gastrointestinal tract. Chronic infection of gastric epithelial cells by Helicobacter pylori (H. pylori) is a major risk factor for human gastric cancer (GC) where Cav1 is frequently down-regulated. However, the function of Cav1 in H. pylori infection and pathogenesis of GC remained unknown. We show here that Cav1-deficient mice, infected for 11 months with the CagA-delivery deficient H. pylori strain SS1, developed more severe gastritis and tissue damage, including loss of parietal cells and foveolar hyperplasia, and displayed lower colonisation of the gastric mucosa than wild-type B6129 littermates. Cav1-null mice showed enhanced infiltration of macrophages and B-cells and secretion of chemokines (RANTES) but had reduced levels of CD25⁺ regulatory T-cells. Cav1-deficient human GC cells (AGS), infected with the CagA-delivery proficient H. pylori strain G27, were more sensitive to CagA-related cytoskeletal stress morphologies (“humming bird”) compared to AGS cells stably transfected with Cav1 (AGS/Cav1). Infection of AGS/Cav1 cells triggered the recruitment of p120 RhoGTPase-activating protein/deleted in liver cancer-1 (p120RhoGAP/DLC1) to Cav1 and counteracted CagA-induced cytoskeletal rearrangements. In human GC cell lines (MKN45, N87) and mouse stomach tissue, H. pylori down-regulated endogenous expression of Cav1 independently of CagA. Mechanistically, H. pylori activated sterol-responsive element-binding protein-1 (SREBP1) to repress transcription of the human Cav1 gene from sterol-responsive elements (SREs) in the proximal Cav1 promoter. These data suggested a protective role of Cav1 against H. pylori-induced inflammation and tissue damage. We propose that H. pylori exploits down-regulation of Cav1 to subvert the host's immune response and to promote signalling of its virulence factors in host cells.

Infection with the bacterium Helicobacter pylori (H. pylori) mainly affects children in the developing countries who are at risk to progress to gastric cancer (GC) as adults after many years of persistent infection, especially with strains which are positive for the oncogenic virulence factor CagA. Eradication of H. pylori by antibiotics is a treatment of choice but may also alter the susceptibility to allergies and other tumor types. Thus, novel diagnostic or prognostic markers are needed which detect early molecular changes in the stomach mucosa during the transition of chronic inflammation to cancer. In our study, we found that the tumor suppressor caveolin-1 (Cav1) is reduced upon infection with H. pylori, and CagA was sufficient but not necessary for this down-regulation. Loss of Cav1 was caused by H. pylori-dependent activation of sterol-responsive element-binding protein-1 (SREBP1), and this event abolished the interaction of Cav1 with p120 RhoGTPase-activating protein/deleted in liver cancer-1 (p120RhoGAP/DLC1), a second bona fide tumor suppressor in gastric tissue. Conclusively, Cav1 and DLC1 may constitute novel molecular markers in the H. pylori-infected gastric mucosa before neoplastic transformation of the epithelium.

[Helicobacter pylori population characteristic in patients with diseases of gastrointestinal tract]

AIM

Study H. pylori strains circulating in St. Petersburg among patients with various gastrointestinal tract pathology as well as study of frequency of infection by H. pylori based on serological markers data among this group of patients.

MATERIALS AND METHODS

By using serological method 162 individuals with various chronic diseases of stomach and duodenum were examined. The presence in blood serum of IgG against H. pylori bacterial antigen and IgG against its toxin--CagA was studied. 129 patients were examined bacteriologically, biopsy samples of stomach mucous membrane were studied. PCR in real time format was used for study of H. pylori strains (49) and biopsy samples (36) of stomach mucous membrane.

RESULTS

The analysis performed showed that on the territory of St. Petersburg H. pylori strains containing cagA gene predominate (81.63% of the isolated strains). Genotyping of strains by vacA showed that s1m1 genotype was more frequent (in 57.14% of cases). The fraction of CagA positive strains in patients in St. Petersburg is maximum for stomach cancer (90.8%), whereas for peptic ulcer disease and gastritis it is 64.7% and 72.2%, respectively. In patients with stomach and duodenum pathology the parameters of seropositivity for H. pylori were significantly higher than in individuals without clinical manifestations of H. pylori infection (86.72% against 65.09%; p < 0.05).

CONCLUSION

The data obtained on increase of fraction of CagA positive strains among H. pylori circulating in St. Petersburg determine the importance of conducting eradication H. pylori.

[Evaluation of the effectiveness of immunomodulating therapy in children with chronic gastroduodenitis]

The article assesses the effectiveness of administering immunomodulating drug cycloferon in patients aged 10 to 16 years with chronic gastroduodenitis. It is established that the use of cycloferon in children with virus-associated chronic gastroduodenitis leads to a significant increase in T- and B-lymphocyte populations in mucous membranes of the stomach and duodenum, and contributes to the elimination of viruses. This results in reduced severity and activity of inflammation in the mucous membranes and decreases clinical manifestations of the disease.

[Subpopulations and phagocytic activity of monocytes in chronic gastroduodenitis in children]

There was conducted a study of the phagocytic activity, immunophenotype and peripheral blood monocytes by flow cytometry in children with chronic gastroduodenitis associated with Helicobacter pylori, as well as the association of Helicobacter pylori with fungi of the genus Candida and markers of secondary immune deficiency. The differential changes in the structure of circulating profile of monocytes were revealed, that indicate the pathogenetic significance of these disorders in chronic gastroduodenitis with H. pylori etiology, as well as at association of Helicobacter pylori with fungi of the genus Candida. Violations of the phagocytic activity of monocytes in chronic gastroduodenitis in children are associated with depression of different stages of phagocytosis--capture functions, mobilization, killing, intracellular biocidity. A severe depression in phagocytic activity of monocytes occurs in CGD associated with Hp and fungi of the genus Candida.

Study of regulatory T-cells in patients with gastric malt lymphoma: influence on treatment response and outcome

Purpose

FOXP3+ regulatory T cells (Treg) play an essential role in modulating host responses to tumors and infections. The role of these cells in the pathogenesis of MALT lymphomas remains unknown. The aims of the study were to quantify the number of infiltrating FOXP3+ and CD3+ cells in patients with gastric MALT lymphoma at diagnosis and to study kinetics of these cells and CD20+ tumor cells after treatment and during long-term follow-up.

Methods

FOXP3+, CD3+ and CD20+ cells were analyzed by immunohistochemistry and the number of cells was quantified using a micrometric ocular. Samples of 35 patients with gastric MALT lymphoma at diagnosis and after treatment were included. Diagnostic samples were compared to 19 cases of chronic gastritis and diffuse large B-cell lymphoma (DLBCL) of the stomach.

Results

The median number of FOXP3+ infiltrating cells was higher (27 cells/cm²) in gastric MALT patients than in DLBCL (10 cells; p = 0.162) but similar to chronic gastritis (20 cells; p = 0.605). No characteristic or specific distribution pattern of infiltrating FOXP3+ cells was found. Gastric MALT lymphoma patients responding to bacterial eradication therapy had higher number of FOXP3+ cells at study entry. Kinetics of both infiltrating FOXP3+ cells and tumor CD20+ cells were strongly dependent on the treatment administered.

Discussion

Gastric MALT lymphomas have a number of Treg cells more similar to chronic gastritis than to DLBCL. Patients with higher number of tumor infiltrating FOXP3+ cells at study entry seem to have better response to antibiotics. Kinetics of Treg and tumor cells are influenced by type of treatment.

Successful treatment of eosinophilic gastroenteritis with clarithromycin

Eosinophilic gastroenteritis (EGE) is an uncommon disease characterized by eosinophilic infiltration of the gastrointestinal tract, which is usually associated with abdominal pain, diarrhea, ascites, and peripheral eosinophilia. Steroids remain the mainstay of treatment for EGE, but symptoms often recur when the dose is reduced. Macrolides have immunomodulatory effects as well as antibacterial effects. The immunomodulatory effect results in inhibition of T-lymphocyte proliferation and triggering of T-lymphocyte and eosinophil apoptosis. Macrolides also have a steroid-sparing effect through their influence on steroid metabolism. We report a rare case of EGE, which relapsed on steroid reduction but improved following clarithromycin treatment.