Helicobacter pylorirepresents a pathogen causing chronic infection in around a half of the global human population, which manifestations vary from asymptomatic infection to developing gastritis and peptic ulcer. The data accumulated suggest that overt clinical types of this infection are associated with lost immunoregulation and increased pro-inflammatory cell-mediated immune response triggered byH. pylori-specific T helper cells. Here, we examined the degree of peripheral blood CD4+T cell maturity and related expression of chemokine receptors involved in migration to gastrointestinal tract (CCR9 and CCR6), as well as Тand B-cell zones of lymphoid organs (CCR7 and CXCR5). It was shown that overtH. pylori-infection was coupled to changes in expression pattern of chemokine receptors on T helper cells. In particular, percentage of mature CD4+CD45RO+T cells bearing CCR9 and immature CD4+CD45RO–Т cells expressing CXCR5 was increased in peripheral blood of patients with chronic gastroduodenitis. However, increased amount of activated mature CD4+CD45RO+ICOS+T cells was observed in patients with chronic gastroduodenitis comorbid with peptic ulcer that was also associated with elevated amount of mature CCR6+T helpers (mainly CD4+CD45RO+CCR7–CCR6+cells) and follicular T helper cells as well as emerging minor CD4+CD45RO+CXCR5+CCR6+.T cell subset, not affecting CD4+CCR9+Т cells. Thus, the data obtained evidence that tissue-specific T-helper cell migration is controlled separately in ofH. pylori-associated diseases.

We previously found that the number of CCR6 + T-helpers with the phenotype of effector/effector memory T cells increases in the blood of patients with H. pylori -associated peptic ulcer. The mature phenotype and the expression of the chemokine receptor CCR6, which is involved in migration of lymphocytes to the inflamed mucous membrane of the gastrointestinal tract, suggests that these cells are involved in the immune response observed in this clinical condition. To better understand the pathogenetic role of these cells, it is necessary to study their functional activity, specifically, the production of pro-inflammatory cytokines involved in the pathogenesis of the disease. The aim of the study was to evaluate changes in the blood level of pro-inflammatory types of mature CCR6 + T-helpers in H. pylori -associated peptic ulcer disease. Materials and Methods. CCR6 + T-helpers were isolated from the blood by using immuno-magnetic separation adapted to this study. The number of T-helpers of types 1 and 17 (Th1 and Th17) and cells with mixed properties of Th1 and Th17 (Th1/Th17) was determined by intracellular cytokine assay. Results. Initially, we planned to activate unseparated peripheral blood mononuclear cells ex vivo and evaluate the number of cytokine producers among mature CCR6 + T-helper cells by gating them during the flow cytometry. However, dramatic changes in the phenotype of T-helpers upon activation did not allow us to reliably identify the cells of interest . Subsequently, we used a two-stage immunomagnetic separation procedure to obtain functionally active mature CCR6 + T-helpers with a purity of >90%. The quantitative yield of these cells from the blood of patients with gastric and duodenal peptic ulcer associated with H. pylori was 9 times higher than that from the blood of healthy donors. Activation of CCR6 + T-helpers purified from blood of ulcer patients revealed an increased content of Th1, Th17, and Th1/Th17. One ml of the patient’s blood yielded 18.1 times more CCR6 + Th1, 19.4 times more CCR6 + Th17, and 21.1 times more CCR6 + Th1/Th17 compared with the blood of healthy subjects. Conclusion. The content of mature CCR6 + T-helper cells with pro-inflammatory activity significantly increases in the blood of patients with peptic ulcer associated with H. pylori infection.

The authors have analyzed research works, both by domestic and foreign researchers that dwell on frequency of H.pylori being resistant to antibacterial medications, the reasons for its occurrence, methods applied to determine it and ways to overcome it. Over the last 15 years there has been a growth in frequency of detecting H.pylori that was resistant to basic antibiotics used to eradicate the pathogen. The authors have established geographical diversity in resistance related to antibiotics intake by population. Bacteriological technique is the most valid for determining H.pylori sensitivity; however, it is rather difficult to apply it due to complicated procedures for the microorganism cultivation. Therefore, molecular-genetic techniques are widely used. H.pylori resistance to Clarithromycin has great practical significance as this antibiotic is able not only to produce antibacterial effects but also to destroy biofilms. Helicobacter that was resistant to Clarithromycin was the least frequently detected in northern European countries (1-3 %); it was the most frequently detected in Southern Europe, Asia,. Research performed in several Russian regions revealed significant variations in frequency of detecting H.pylori resistant to Clarithromycin (5-40 %) and a growth in dynamics of this detection (from 5 to 15 %). Frequency of detecting helicobacter resistance to another widely used medication, Metronidazole, is also different in different geographic regions; it amounts to 17 % in Europe, 24 % in Russia, and 92 % in Africa. H.pylori still has low resistance to Amoxicillin and another reserve medication, Rifabutin.The article also dwells on probable ways to overcome non-sensitivity of the pathogen to antibiotics and the necessity to develop procedures for treating H.pylori infection based on the results of examining the pathogen sensitivity with standardized techniques performed in different regions. Efficient H.pylori eradication reduces inflammation in the gastric mucosa, prevents ulcer formation and atrophy and reducers risks of stomach cancer.

Helicobacter pylori is a widely spread pathogenic microorganism. It penetrates the mucous tunic of the stomach and the duodenum and causes diseases in the gastrointestinal tract, including oncologic ones. This agent is able to be chronically persistent in a body and frequently there are no apparent symptoms of it; therefore, it is difficult to detect this pathogen in due time. Risk analysis related to occurrence and development of various pathologies associated with Helicobacter pylori, revealed that their clinical course was to a great extent determined by an immune response that emerged after infection. There are data that Helicobacter pylori is able to influence protective immune reactions making their balance to move to an increase in immune-suppressive components, for example, increased concentrations of T-regulatory cells and cytokines produced by them. However, some data can be found on Helicobacter pylori ability to induce anti-inflammatory responses which include those associated with T-helpers of the 1st and 17th types. Our research goal was to reveal peculiarities of effects produced by this pathogen on γ-interferon as one of basic products by 1st type T-helpers and on contents of the 17th type T-helpers determined as cells belonging to CD4 + CD161 + and CD4 + IL17 + phenotypes under direct contacts between bacteria and lymphocytes. Our research objects were clinical isolates of Helicobacter pylori and blood samples taken from people without helicobacter infection in their case history. We extracted lymphocytes with immunomagnetic separation out of mononuclear blood cells obtained via functioning in density gradient. Their concentrations were assessed with cytofluorometry; cytokines products, with enzyme-linked immunosorbent assay. We showed that CD4 + CD161 + and CD4 + IL17 + cells content didn't change when they were cultivated together for 18 hours under influence exerted by Helicobacter pylori, while products of γ-interferon increased considerably. It can probably be related to activation of the 1st type T-helpers under effects produced by direct contact with bacteria. However, we didn't detect any activation of the 17th type T-helpers. Therefore, we can assume that effects produced by Helicobacter pylori on T-helpers under direct contact cause a response in a form of the 1st type T-helpers activation.

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