Role of autophagy defects and significance of adherent-invasive <i>Escherichia coli</i> in Crohn's disease development

The aim of review. To present new data on a role of molecular genetic disorders of innate immunity at Crohn's disease (CD), and to demonstrate the role of adherent-invasive Escherichia coli (AIEC) as the microorganisms potentially involved in CD development.Summary. According to modern concept, etiology of CD has complex nature and is determined by genetic predisposition, infectious agents and environmental factors. Alteration of autophagy process (defects of NOD2/ CARD15, ATG16L1, IRGM genes) is one of genetically determined disorders of innate immunity typical for CD. Besides that intestinal dysbiotic disorders associated with elevation of quantity of microorganisms, possessing pathogenic potential, in particular AIEC is characteristic for CD. This phenotype of microorganisms has capacity of adhesion to mucosal epithelial cells, invasion, and active replication inside macrophages. In patients with genetic predisposition AIEC replication in macrophages at reduced clearance of microorganisms due to alteration of autophagy process can induce the unsound immune response with development inflammatory changes characteristic for CD.Conclusion. Intestinal dysbiosis associated with elevation of quantity of microorganisms, possessing pathogenic potential (AIEC), as well as genetically — determined defects of innate immunity (autophagy alteration) lay in a basis of up-to-date model of CD development. Undoubtedly, such model is most likely relevant only for selected part of CD patients, nevertheless for the present moment it is the basic for the further studying of CD etiopathogenesis

MOLECULAR DOCKING AND MOLECULAR DYNAMICS STUDIES OF THE NOVEL HU PROTEIN DNA BINDING ABILITY INHIBITORS. INSIGHTS INTO THE INHIBITION MECHANISM AND SELECTIVITY

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HOMOLOGY MODELING AND MOLECULAR DYNAMICS STUDIES OF THE OLIGOPEPTIDASE B FROM SERRATIA PROTEAMACULANS. INSIGHTS INTO THE ENZYMATIC ACTIVATION MECHANISM

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STUDYING DEVELOPMENT OF POST-VACCINAL CELLULAR IMMUNITY AGAINST BRUCELLOSIS BY MEANS OF LYMPHOCYTE <i>IN VITRO</i> TESTS USING AN EXPERIMENTAL ANTIGENIC COMPLEX

Regulatory framework and methodological approaches to evaluation of immunological effects of vaccination against brucellosis are not established, and the degree of immunological post-vaccinal rearrangement is not yet developed. Due to leading role of cellular immunity in formation of immune protection against brucellosis, evaluation the cellular response in response to antigenic stimulation may be considered the most informative and objective approach to analysis of immune changes in the body during vaccination. In order to develop the most diagnostically informative methods for design of antigen-stimulation cell tests in vitro, a careful selection of a stimulating agent (antigen) is required, which should have a sufficient activating potential, thus providing specificity of reaction under in vitro conditions. The aim of the present study is to study the in vitro specific activity of a protein-polysaccharide antigenic complex from the Brucella abortus 19 BA strain (BrAg), and an opportunity of its application in order to assess the formation of post-vaccinal cellular immunity against brucellosis.The study was performed with white laboratory mice (n = 50) immunized with the Brucella abortus 19 BA strain. The control group (n = 50) consisted of laboratory mice that received a sterile saline solution in a volume of 0.5 ml. Blood samples were taken from immunized and control animals before vaccination, and 7, 14, 21, and 30 days after immunization. By means of flow cytometry, the activation molecules CD25, CD69, MHC II and CD95, expressed on T lymphocytes (CD3+CD69+, CD3+CD25+, CD3+CD95+, CD3+MHC+) were determined. To observe the development of immunity, the intensity of expression of T lymphocyte activation markers was calculated using the stimulation quotient. BrAg was used for specific in vitro stimulation of T lymphocytes. The liquid brucellosis allergen (brucellin) was used as an antigen for comparison, when studying opportunity of BrAg usage for assessing the postvaccinal immunity development.The following results were obtained: BrAg has pronounced specific activity, it did not cause non-specific in vitro reactions (activation) of T lymphocytes, thus enabling its application as a test antigen when evaluating development of adaptive vaccine immunity against brucella.Experimental testing of brucellosis antigen for carrying out the in vitro antigen-stimulated cellular reactions, aiming for evaluation of post-vaccinal immunity development against brucellosis, showed that the usage of BrAg promotes increase in diagnostic sensitivity of cellular reactions under in vitro experimental conditions. The applied experimental antigen is a quite promising tool for development of laboratory algorithms for brucellosis diagnostics, and assessment of actual vaccination efficiency in cohorts previously vaccinated against brucellosis

Application of Basophil Activation Test with Anthraxin for Laboratory ( <I>in vitro</I>) Diagnostics of Anthrax

Demonstrated is the possibility to use in vitro basophil activation test with anthraxin, with registration of the results by means of flow cytometry, for anthrax diagnostics. This approach seems promising as it provides quantitative assessment of sensitization of the organism and does not cause its additional allergization. The duration of the analysis is 1h. The test is suggested for application, as an express one, for early and retrospective laboratory diagnostics of anthrax, estimation of post-vaccinal immunity

Analysis of Epizootiological-Epidemiological Situation on Brucellosis in the Russian Federation in 2018 and Forecast for 2019

Presented is the analysis of brucellosis incidence among humans and animals in the Russian Federation in 2018. Epizootiological situation in the regions of developed animal husbandry remains reasonably tense. In 2018, as in previous years, the foci of bovine cattle and small ruminant brucellosis were registered in the North Caucasian, Southern Federal Districts, Volga and Siberian Federal Districts, the share of which made up to more than 90% of all registered in Russia potentially hazardous as regards brucellosis areas and cases of the disease in animals. Against the background of long-term unfavorable epizootic condition, the incidence of brucellosis over the past three years was, on average, 14 % lower than the average long-term indicators. The greatest number of cases (94.1 % of the overall Russian incidence) is registered in the administrative subjects of the North Caucasus Federal District, Southern Federal District and Siberian Federal District, which have the maximum levels of brucellosis incidence in cattle (88.9 %) and small ruminants (95 %). In 2019, persistence of epidemiological problems in regard to brucellosis in the subjects of the North Caucasus Federal District (primarily the Republic of Dagestan, Stavropol Territory), the Southern Federal District (the Republic of Kalmykia, Volgograd and Astrakhan Regions), and the Siberian Federal District (the Tuva Republic, the Omsk and Tyumen Regions) is predicted. The number of human cases of brucellosis may be within the range of 290–310 cases (intensive incidence rate per 100 thousand population – 0.21)

Brucellosis: Trends in the Development of Situation in the World and Forecast for 2022 in the Russian Federation

An analysis of trends in the development of situation on brucellosis in the world over past decade and the data on the main risk factors for the occurrence of epidemiological complications regarding this infection in various regions of the world are provided in the paper. An expert assessment of the current epizootiological and epidemiological situation on brucellosis, the coverage of population and animals with immunization in the Russian Federation is given. Over 9 months of 2021, 210 potentially hazardous as regards brucellosis in cattle areas and 24 sites – as regards brucellosis in small ruminants – were registered in Russia. Compared to the same period in 2020, there was a decrease in the number of newly identified hazardous sites for bovine brucellosis by 35.8 % (117 areas). However, long-term upward trend in epizootiological adversity for bovine brucellosis in Russia persists. The epidemiological situation on brucellosis in the country for the period of 2012–2021 is characterized as unfavorable. Decrease in the number of newly detected human brucellosis cases (by 25.1 % of long-term average values) is observed against the background of persistent unfavorable epizootic conditions for brucellosis among epidemiologically significant species of small ruminants and cattle in regions with developed animal husbandry. In 2021, clusters of human cases were registered in the Republic of Dagestan and Penza Region. In the Republic of Dagestan, against the background of aggravation of epizootiological and epidemiological situation on brucellosis, there was also an alarming trend towards prevalence of a relatively high incidence among minors. The proportion of cases of brucellosis among children under the age of 17 in the Republic amounted to 60.3 % of the total number of minors with newly diagnosed brucellosis in Russia over the past 10 years. Taking into account current epizootic, epidemic situations and the long-term dynamics of the development of situation on  brucellosis in the Russian Federation, the incidence of brucellosis among the population  is predicted to be 10–15 % lower than the average long-term values – 0.18–0.20 per 100000 of the population – in 2022. The number of human cases of brucellosis can range from 250 to 300

Using CAST-test to investigate human specific hypersensitivity to the anthrax pathogen

We present the results of applying functional cytometric test of antigen-stimulated activation basophils to assess specific immunological reactivity in the people with anthrax, and immunized with anthrax vaccine. As a criterion for antigen-specific basophil activation, we measured expression of the CD63 membrane receptor, which reflects the process of anaphylactic basophil degranulation. To determine spontaneous and antigen-induced activation of basophils (CCR3+CD63+), a FlowCAST reagent kit (Buhlmann laboratories AG, Switzerland) was used. Anthraxin, an experimental anthrax allergen (a hydrolysate the Bacillus anthracis STI-1 strain), manufactured by the Stavropol Anti-Plague Institute, was used as a specific antigen. As based on clinical and experimental data, a threshold value of &gt; 10% of anthraxin-activated (CCR3+CD63+) basophils was accepted for the in vitro immunodiagnostic CAST test, as a laboratory criterion for the subjects exhibiting specific immune response, i.e., IgE-mediated sensitization. It was shown that, in anthrax patients within one week after onset of the disease (3-7 days), a positive CAST result was obtained in 92.3% cases; the levels of specific basophil activation with anthraxin averaged 37.9% (12.01 ÷ 78.9%). Immunological examination of individuals three weeks (21 days) after vaccination against anthrax revealed CAST-positivity in all the vaccinated persons. Intensity of anthraxin-induced basophil activation the vaccinated subjects was ranged from 10.87 to 30.03%, averaging 17.86%. The overall values of spontaneous and specific activation ranged within 12.39 ÷ 41.46%. The study opens prospectives for implementation of basophil antigenic activation test in the Flow CAST format in diagnostics of anthrax and to identify specific immune rearrangements after vaccination in humans, as an index of actual vaccination rates. Usage of CAST test with anthraxin makes it possible to identify anthrax patients at the early stages (2-4 days after onset of the disease) including, among patients with an increased CCR3+CD63+ background values, evaluation of immunological efficiency in the cohorts at risk for vaccination. At the same time, it was found that a significant decrease in diagnostic sensitivity of CAST test could be observed in the patients immune to anthrax pathogen who received intensive antibacterial and pathogenetic therapy at the early stages of infection, including glucocorticosteroids (anti-inflammatory drugs) and desensitizing agents that inhibit the degree of hypersensitivity development and its expression

Analysis of Brucellosis Incidence and Molecular-Genetic Characteristics of Brucella Population in the Territory of the Russian Federation

An analysis of brucellosis incidence in Russia in 2013–2022 and the data on genetic diversity of Brucella melitensis and Brucella abortus populations isolated in Russia in 1939–2022 are provided in the review. Over the past decade, the epidemiological situation in Russia has been characterized as unstable against the background of persistent unfavorable conditions for brucellosis in cattle and small ruminants. During the period of 2013–2022 (9 months), 4298 epizootic foci as regards brucellosis in cattle (89164 sick animals) and 371 as regards brucellosis in small ruminants (13569) were registered. The largest number of epizootic brucellosis foci was recorded in the North-Caucasian and Southern Federal Districts. In 2013–2022, on average, 327 cases of brucellosis among people were registered annually, the incidence rate per 100 000 of the population was 0.24. Up to 70–90 % of brucellosis cases were detected in the south of the European part of the country. A trend towards deterioration of the situation on brucellosis in Volga (Penza and Samara Regions) and Central (Smolensk, Voronezh and Tula Regions) Federal Districts is observed. There is a connection between the intensity of epidemic manifestations of brucellosis and the level of anthropurgic enzooty of territories. In 2022, 467 cases of brucellosis were reported (0.32 per 100 000 of the population), which is 42.8 % higher than annual average values over 10 years. In 2023, a measure of stability of incidence rates, by 20–25 % above average long-term values, is to be expected. Incidence of brucellosis in humans will be within the range of 380–410 cases (0.26–0.28 per 100 000 of the population). The results of genotyping of B. melitensis strains point to an increase in the proportion of isolates with an MLVA-profile characteristic of strains from enzootic as regards brucellosis countries of Middle East and North Africa over past 20–25 years, which can indicate importation (introduction) of the infection from these territories to Russia through small ruminants and/or biomaterial from them

Genome analysis of E. coli isolated from Crohn's disease patients

© 2017 The Author(s). Background: Escherichia coli (E. coli) has been increasingly implicated in the pathogenesis of Crohn's disease (CD). The phylogeny of E. coli isolated from Crohn's disease patients (CDEC) was controversial, and while genotyping results suggested heterogeneity, the sequenced strains of E. coli from CD patients were closely related. Results: We performed the shotgun genome sequencing of 28 E. coli isolates from ten CD patients and compared genomes from these isolates with already published genomes of CD strains and other pathogenic and non-pathogenic strains. CDEC was shown to belong to A, B1, B2 and D phylogenetic groups. The plasmid and several operons from the reference CD-associated E. coli strain LF82 were demonstrated to be more often present in CDEC genomes belonging to different phylogenetic groups than in genomes of commensal strains. The operons include carbon-source induced invasion GimA island, prophage I, iron uptake operons I and II, capsular assembly pathogenetic island IV and propanediol and galactitol utilization operons. Conclusions: Our findings suggest that CDEC are phylogenetically diverse. However, some strains isolated from independent sources possess highly similar chromosome or plasmids. Though no CD-specific genes or functional domains were present in all CD-associated strains, some genes and operons are more often found in the genomes of CDEC than in commensal E. coli. They are principally linked to gut colonization and utilization of propanediol and other sugar alcohols