One of the important directions for increasing the immunogenic properties of vaccine strains against highly dangerous infections is the search for adjuvants that not only stimulate the immunological effectiveness of vaccination, but can also provide a metabolic correction of the vaccination process. Organoselenium compounds have immunotropic properties and an antioxidant effect, and therefore, the study of the effect of the organoselenium compound 2,6-dipyridinium-9-selenabicyclo[3.3.1]nonane dibromide (974zh) on the activity of the TLR2 and TLR4 gene expression by macroorganism cells of experimental animals immunized with Yersinia pestis EV NIIEG vaccine strain, is a current area of research.The aim of the work. To assess the TLR2 and TLR4 gene expression by cells of the immune phagocyte system of experimental animals immunized with the Y. pestis EV vaccine strain against the background of immunomodulation with the organoselenium compound 974zh.Materials and methods. The study was carried out on 125 certified outbred white mice. Biological material (blood, spleen) was disinfected, and the spleen was homogenized. RNA isolation and reverse transcription were performed using commercial reagent kits. The expression level of the TLR2 and TLR4 genes was determined using real-time polymerase chain reaction with specific primers.Results. When assessing innate immunity using the example of blood and spleen cells of animal models, features of the TLR2 and TLR4 gene expression were revealed in response to the introduction of the Y. pestis EV vaccine strain against the background of immunomodulation with the 974zh. It was found that 974zh induces a statistically significant increase in TLR2 gene expression when co-administered with Y. pestis EV at a dose of both 104 CFU and 103 CFU.Conclusion. Y. pestis EV against the background of immunomodulation with 974zh, stimulates the expression of the TLR2 and TLR4 genes, which may indicate an increase in the immunogenic properties of the Y. pestis EV vaccine strain under the influence of this preparation.

The polymorphism of HLA class II genes was studied in COVID-19 survivors and vaccinated people. Six allelic variants of DQA1, 10 of DQB1, and 11 of DRB1 were identified. The DQA1*05:01 allele predominated in vaccinated volunteers and the DQA1*02:01, *01:03, and DQB1*06:02-8 alleles predominated in convalescents. In the groups with DQA1*01:01, *05:01 and *06:01 alleles, a high proportion of individuals seropositive for SARS-CoV-2 S protein was found. In the group with DQA1*02:01 allele, 40% of volunteers were found to have IgM and a significantly lower quantity of IgG to N protein of coronavirus. Comparative analysis showed a statistically significant increase in IL-10 levels in carriers of the DQA1*01:01 allele, which may indicate the influence of this allele on cytokine production. Further study of the immune response indices and their association with HLA class II gene polymorphism will provide better understanding of the mechanisms of COVID-19 immunogenesis.

Relevance . COVID-19 is accompanied by high production of cytokines - immune molecules, imbalanced regulation of which leads to disruption of the immune response. Therefore, the study of cytokine status in both vaccinated and re-vaccinated patients is necessary to develop an immunoprophylaxis strategy for COVID-19. Aim. To evaluate the cytokine status in COVID-19 survivors and vaccinated employees of a health care facility against this disease. Materials and Methods. Production levels of cytokines (IL-4, IL-10, IFN-γ and TNF-α) were determined by quantitative enzyme immunoassay in serum of 144 volunteers. Results and discussion . A significant 1.5-fold increase in IL-10 and 2.0-fold increase in TNF-α was found in the group of re-invaccinated overinfected volunteers, and a 2.0-fold decrease in IL-4 compared with the vaccinated group. An inverse correlation between IL-4 and IFN-γ levels and timing after the disease was detected. A significant decrease in IL-4 in survivors (Omicron variant) and an increase in IL-10 in the survivors at the beginning of the pandemic as compared to other re-vaccinees was established. In the vaccinated group, regardless of the vaccine used, IL-10 and TNF-α decreased significantly after revaccination. No statistically significant differences were found between the cytokine status parameters in the survivors before and after vaccination. The predominance of the cellular component of immunity was established in all the examined groups, and the highest proportion of persons with a humoral immune response was detected among the vaccinated volunteers, while the highest proportion of persons with a mixed immune response was detected among the overexperienced non-vaccinated patients. Conclusions . The results obtained supplement the available data on coronavirus infection and indicate the need for further research.

Background. There are many aspects of the development of immunity to the SARSCoV-2 virus, that remain poorly understood, like the influence of age-related characteristics on the intensity of immunity and the course of the disease. Studies of the state of immunity are widely used, mainly in the adults. But questions of the patho- and immunogenesis in children remain unsolved. Determining the nature of seroconversion of antibodies to SARS-CoV-2 in this age group is important information for serological monitoring for targeted immunoprophylaxis of the population and forecasting the epidemic situation in the region.The aim. Evaluation of the dynamics of seroprevalence of specific antibodies to SARS-CoV-2 in children of the Irkutsk region during the pandemic of a new coronavirus infection.Materials and methods. Study was conducted among the child population of the Irkutsk region in the period June 2020 – December 2021 as part of the Rospotrebnadzor project to assess population immunity to SARS-CoV-2 in the population of the Russian Federation. The content of antibodies to SARS-CoV-2 was determined by ELISA using native commercial test systems.Results. Population immunity among the child population of the Irkutsk region was characterized by an upward trend from 7.8 % at stage 1 to 98.4 % at stage 6 of the study. IgG to SARS-CoV-2 remained in 72.8 % and formed in 25.6 % of previously seronegative children. Antibodies were detected in 66.1 % of cases and persisted for up to 10–15 months after COVID-19 infection. The proportion of asymptomatic forms of infection among seropositive volunteers was 69.5 %, which determines the high intensity of the latent epidemic process.Conclusion. The level of seroprevalence was 98.4%. The current results of serological monitoring serve as a scientific basis for adjusting the list and scope of management decisions on the organization of preventive anti-epidemic measures, including vaccination.

Introduction. An urgent direction is the search for means that increase the effectiveness of the Y. pestis EV NIIEG vaccine and reduce the side pathological manifestations caused by it. Organoselenium compounds have immunotropic properties and increase the antioxidant potential of the body, as well as have an antidystrophic effect and an antiallergic effect. Materials of the study of the immunomodulating effect of the experimental selenium-containing compound 2,6-dipyridinium-9-selenabicyclo[3.3.1]nonane dibromide (974zh) on the macroorganism of laboratory animals are presented.The aim. To evaluate the effect of the organoselenium compound 974zh on the structural rearrangement of the organs of experimental animals in the dynamics of the vaccine process caused by Y. pestis EV.Methods. The study was carried out on 70 certified outbred white mice. Histological material (thymus, lymph nodes, spleen, adrenal glands, liver) was embedded in paraffin, semi-thin sections were stained with hematoxylin and eosin, thionin, and by the Brachet method. The severity of pathological changes in the liver and adrenal glands, proliferation of plasma cells and structural changes in immunocompetent organs (thymus, lymph nodes and spleen) were assessed. Microphotography and quantitative analysis were performed using MoticImagesPlus 2.0. Statistical processing was carried out using the computer program Statistica.Results. It has been established that the combined administration of 974zh and Y. pestis EV leads to morphological and functional restructuring of immunocompetent organs, enhances the proliferation of plasma cells in the spleen and lymph nodes, and eliminates negative changes in the liver and adrenal glands. Conclusion. Thus, the 974zh preparation enhances the immunogenic effect of the Y. pestis EV vaccine strain, increasing the T- and B-dependent zones of the spleen and lymph nodes, increasing the proliferation of plasma cells, and also significantly reduces pathological changes in the liver and adrenal glands.

We performed a seroepidemiological survey of the level and structure of population immunity to SARS-CoV-2 among employees of medical institution in the Irkutsk region during the COVID-19 pandemic. Seroprevalence assessment was organized from May 2020 to April 2021. The level of antibodies to SARS-CoV-2 was measured by ELISA. It was found that 139 (46%) of 299 examined workers were seropositive, including 50 (36%) vaccinated against COVID-19, 75 (54%) patients diagnosed with COVID-19, and 14 (10%) asymptomatic cases of SARS-CoV-2. The results obtained should be taken into account when predicting the dynamics of the epidemic process and organizing preventive (antiepidemic) measures, including vaccination.

Background. Improving the methodology of immunological monitoring in natural foci of plague in the Russian Federation and adjacent territories to increase the effectiveness of epidemiological surveillance of plague is an urgent line of research. The lack of correlation between the production of specific antibodies to the capsular antigen (F1) ofthe plague microbe with other indicators of the state of cellular defense reactivity indicates the need to search for new informative and accessible markers for assessing anti-plague immunity.Objective: to evaluate possibility of using the complex preparation (F1 and cell membranes) evaluate the possibilities of using an artificial antigenic complex based on F1 and cell membranes (CM) of the plague microbe in antigen-specific tests in vitro in people vaccinated against plague.resu. The study involved 153 volunteers living in the territory enzootic for plague (the village of Khandagayty ofthe Ovyur kozhuun of the Tyva Republic and the village of Kosh-Agach of the Kosh-Agach district of the Altai Republic). The study included the determination of spontaneous and mitogen-induced production of cytokines (IFN-γ, IL-4, TNF-α) by blood cells, titers of specific IgG antibodies to the capsular antigen F1 of the plague microbe and concentrations ofthe main classes of immunoglobulins (IgM, IgG, IgA and IgE) in blood serum, as well as immunophenotyping of blood lymphocytes (CD3, CD4, CD8, CD16, CD19).Results. Comparative assessment of the level of cytokines (TNF-α, IFN-γ and IL-4) in spontaneous/induced F1+CM Y. pestis tests revealed a statistically significant increase in the production of cytokines TNF-α and IFN-γ in the antigeninduced tests compared with spontaneous (p < 0.01).Conclusion. Thus, the effectiveness of the use of artificial antigenic complex based on F1 and cell membranes ofthe plague microbe has been shown to assess the production of cytokines in antigen-specific cell tests in vitro, which justifies the need for further research.

Пандемия COVID-19 в мире и в России была и остается главным событием в настоящее время. В связи с этим изучение закономерностей развития и проявлений эпидемического процесса новой короновирусной инфекции COVID-19 является актуальным направлением исследований. Важная роль в борьбе с этим вирусным заболеванием отводится изучению развития популяционного иммунитета к вирусу SARS-CoV-2 с целью оценки динамики серопревалентности и процесса формирования постинфекционного гуморального иммунитета, прогноза развития эпидемиологической ситуации, выявления особенностей эпидемического процесса, а также планирования мероприятий по специфической и неспецифической профилактике заболевания. Цель исследования – определение уровня и структуры популяционного иммунитета к SARS-CoV-2 среди населения Иркутской области в период пандемии COVID-19. В рамках проекта Роспотребнадзора по оценке популяционного иммунитета к SARS-CoV-2 у населения Российской Федерации проведены исследования среди населения Иркутской области в периоды с 23.06.2020 по 19.07.2020 г. (1 этап), с 16.09.2020 по 25.09.2020 г. (2 этап) и с 7.12.2020 по 18.12.2020 г. (3 этап) с учетом протокола, рекомендованного ВОЗ. Содержание антител к SARS-CoV-2 определяли методом иммуноферментного анализа с использованием набора реагентов для анализа сыворотки или плазмы крови человека на наличие специфических иммуноглобулинов класса G к нуклеокапсиду вируса SARS-CoV-2 производства ФБУН ГНЦПМиБ Роспотребнадзора (г. Оболенск). Показано, что в период эпидемического подъема заболеваемости COVID-19 сформировался невысокий уровень серопревалентности (1 этап – 5,8±0,5%; 2 этап –12,1±0,7%), а в условиях длительного максимального роста заболеваемости – 25,9±1,0% (3 этап). Значительная доля бессимптомных форм инфекции на первых двух этапах исследования (1 этап – 81,2±3,2%, 2 этап – 90,9±1,9%) характеризует высокую интенсивность скрыто развивающегося эпидемического процесса. Высокий уровень IgG у перенесших COVID-19 сохранялся в среднем от 3 до 4,5 месяцев. Результаты оценки популяционного иммунитета к вирусу SARS-CoV-2 у населения Иркутской области свидетельствуют о том, что уровень серопревалентности на 3 этапе исследования составил 25,9%. После перенесенного заболевания в среднем у 41,6% лиц, антитела не выявлены. Полученные результаты следует учитывать при организации профилактических мероприятий, включая вакцинацию, и прогнозирование заболеваемости.

Background. The ongoing COVID-19 pandemic in the world and in Russia remains the main event in 2020. A comprehensive study of the patterns of development and manifestations of the epidemic process of the new coronavirus infection COVID-19 is an urgent line of research. One of the important aspects of the fight against COVID-19 is the study of population immunity to the SARS-CoV-2 virus in order to assess seroprevalence and the formation process of post-infectious humoral immunity to SARS-CoV-2, forecast the development of the epidemiological situation, identify the features of the epidemic process, as well as planning measures for specific and non-specific disease prevention. The aim of the research is to determine the level and structure of population immunity to SARS-CoV-2 among the humans of the Irkutsk region during the COVID-19 epidemic. Materials and methods. As part of the Rospotrebnadzor project to assess population immunity to SARS-CoV-2 in the population of the Russian Federation, research is being conducted among the population of the Irkutsk region in the periods from 06/23/2020 to 07/19/2020 (stage 1), from 09/16/2020 to 09/25/2020 (Stage 2) and from 12/07/2020 to 12/18/2020 (stage 3), taking into account the reacted one recommended by the WHO. The content of antibodies to SARS-CoV-2 was determined by ELISA using a set of tests for human serum or plasma for specific immunoglobulins of class G to the nucleocapsid of the SARS-CoV-2 virus produced by FBUN GNCPMiB Rospotrebnadzor (Obolensk). The results of a research of the humoral immunity of volunteers show that during the period of an epidemic rise in the incidence of COVID-19 in the Irkutsk region, a low level of seroprevalence was formed (stage 1 – 5.8 ± 0.5%, stage 2 – 12,1 ± 0,7%), and in conditions of a long-term maximum increase in the incidence rate ¬– 25,9±1,0% (stage 3). A significant proportion (stage 1 – 81,2±3,2%, stage 2 – 90.9 ±1,9%) of asymptomatic forms of infection characterize the high intensity of the latently developing epidemic process in the first two stages. High levels of IgG in reconvalescents of COVID-19 persisted for an average of 3 to 4.5 months. Conclusion. The results of assessing the population immunity to the SARS-CoV-2 virus in the population of the Irkutsk region indicate that the seroprevalence level at the 3rd stage of the research was 25.9%. After the disease, on average, 41.6% of persons did not detect antibodies. The results obtained should be taken into account when organizing preventive measures, including vaccination, and predicting morbidity.

Relevance. In Russia, the live plague vaccine (LPV) is used for specific prophylaxis of plague. Immunological monitoring of humans vaccinated by LPV in order to search for informative diagnostic markers, as well as to improve the tactics of epidemiological surveillance of plague enzootic territories is an urgent area of research.The aim is to assess the parameters of cellular and humoral immunity in humans revaccinated by LPV who permanently reside on territory of the Tuvinian natural plague focus.Materials and methods. The study involved 76 volunteers from the Republic of Tuva, revaccinated by LPV. Blood sampling was performed before vaccination and 1, 3, and 6 months after revaccination. The study included the determination of cytokine production (IFN-γ, IL-4, TNF-α), specific antibodies, immunoglobulins (IgM, IgG, IgA and IgE) and lymphocyte subpopulation composition (CD3, CD4, CD8, CD16, CD19, immunoregulatory index).Results. A decrease in IgG and IgM and an increase in IgA were found after vaccination with LPV and their increase after revaccination. Correlation relationships were revealed between immunoglobulins, B cells and IL-4. Revaccination leads to an increase seroconversion. The activation of humoral immunity in humans vaccinated against plague is also evidenced by dynamics of changes in the subpopulation composition: an increase in B-lymphocytes and natural killer cells, a decrease in T-helpers and immunoregulatory index, and cellular immunity stimulation is an increase in spontaneous and induced production of pro- and anti-inflammatory cytokines.Conclusion. It has been shown that LPV is capable of causing the body’s immune restructuring and activating the cellular and humoral mechanisms of immunological protection. For a complete understanding of the development and preservation of antiplague immunity, it is necessary to continue the annual immunological monitoring of the population living on the territory of the Tuvinian natural plague focus, using additional modern research methods.

Background. Currently, the COVID-19 pandemic in the world and in Russia remains the main event. In this regard, the study of the manifestations of the epidemic process of the new coronavirus infection COVID-19 and the patterns of its development are an urgent area of research. In the fight against this viral disease, an important role is assigned to the study of the development of population immunity to the SARSCoV-2 virus, which will make it possible to assess the dynamics of seroprevalence and the formation of post-infectious humoral immunity, forecasting the development of the epidemiological situation, elucidating the characteristics of the epidemic process, and will also contribute to planning activities for specific and non-specific prevention of the disease.The aim: to determine the dynamics of population immunity to SARS-CoV-2 among the population of the Irkutsk region during the COVID-19 pandemic.Materials and methods. As a part of the Rospotrebnadzor project of assessing population immunity to SARS-CoV-2 in the population of the Russian Federation, the research has being conducted among the population of the Irkutsk region in the periods from June 23, 2020 to July 19, 2020 (Stage 1), from September 16, 2020 to September 25, 2020 (Stage 2), from December 7, 2020 to December 18, 2020 (Stage 3) and from March 8, 2021 to March 14, 2021(Stage 4), taking into account the reacted one recommended by the WHO. The content of antibodies to SARS-CoV-2 was determined by ELISA using a set of tests for human serum or plasma for specific immunoglobulins of class G to the proteins of the SARS-CoV-2 coronavirus.The results. The research of the humoral immunity of volunteers shows that during the period of an epidemic rise in the incidence of COVID-19 in the Irkutsk region, a low level of seroprevalence was formed (Stage 1 – 5.8 ± 0.5 %, Stage 2 – 12.1 ± 0.7 %), and in conditions of a long-term maximum increase in the incidence rate – 25.9 ± 1.0 % (Stage 3) and 46.2 ± 1.2 % (Stage 4). A significant proportion (Stage 1 – 82.2 ± 3.2 %, Stage 2 – 86.1 ± 2.3 %) of asymptomatic forms of infection characterizes the high intensity of the latently developing epidemic process in the first two stages. High levels of IgG in reconvalescents of COVID-19 persisted for an average of 3 to 5 months.Conclusion. The results of assessing the population immunity to the SARS-CoV-2 virus in the population of the Irkutsk region indicate that the seroprevalence level at Stage 4 of the research was 46.2 %. After the disease, on average, 49.5 % of persons did not detect antibodies. The results obtained should be taken into account when organizing preventive measures, including vaccination, and predicting morbidity.

Background. Currently, during the COVID-19 pandemic, one of the most pressing healthcare problems is to ensure the safety of the population of the Russian Federation. There is insufficient information on the duration and intensity of post-infectious immunity in relation to SARS-CoV-2, especially in case of inapparent (without clinical signs), mild or latent forms of infection.Materials and methods. The study involved 99 volunteers with a laboratory confirmed PCR diagnosis of COVID-19 who were residents of the Irkutsk Region and of other regions of the Russian Federation and arrived to work in Bodaybo on a rotational basis. Also the study included 50 conditionally healthy people living in Irkutsk who had negative PCR results for SARS-CoV-2 RNA presence.Specific IgG and IgM antibodies to SARS-CoV-2 were detected in blood serum by enzyme-linked immunosorbent assay (ELISA) using test systems “ELISA anti-SARS-CoV-2 IgG” (FBUN SSC PMB, Obolensk, Russian Federation), “SARS-CoV-2-IgG-IFA-BEST” and “SARS-CoV-2-IgM-IFA-BEST” (Vector-Best, Novosibirsk, Russian Federation).Results. The results of a study of the humoral immunity of patients with asymptomatic and clinical forms of COVID-19 are presented. The data indicate the production of specific IgG in the blood serum of people in 2–3 weeks after SARSCov-2 infection and reaching its maximum level on the 20–21st day. The seroconversion rate was 94.9 %. It was shown that the geometric mean titer of antibodies in asymptomatic and mild forms of coronavirus infection did not differ statistically and amounted to 1:512 and 1:632, respectively. Higher titers of antibodies (1:1600) were detected in the moderate form.Conclusion. The research results can serve as a basis for studying the dynamics of changes in the indicators of the humoral immune response in patients with COVID-19 and for clarifying the duration of their post- infectious immunity in order to predict the development of the epidemic situation and to ensure the planning of specific prevention.

We studied the expression of activation markers CD25 and CD69 by blood lymphocytes in white mice vaccinated with Brucella abortus 19 BA in antigen-specific tests in vitro. During incubation of blood lymphocytes with brucellosis polysaccharide-protein antigen, a statistically significant increase in the expression of CD25 by B cells and CD69 by T cells was observed; brucellin increased the expression of CD25 by B and T cells. Comparative analysis of the action of antigen preparations B. abortus showed that only brucellin has antigen-specific activity against CD19+CD25+ cells. The used method can be considered as a promising test for evaluation of the effectiveness of brucellosis immunoprophylaxis, which substantiates the need for further research.

Aim. To study the subpopulational structure of blood cells of the experimental animals immunized with thermoextracts (TE) of Brucella abortus in L- and S-form. Materials and methods. Total 100 certified («Vector», Novosibirsk) outbred mice were immunized with B. abortus I-206 TE in L- and S-form in 20 μg protein dose. After 1, 3, 7, 14 and 21 days of observation the phenotypes (CD45, CD3, CD4, CD8, CD19, CD69) of blood cells were detected. Results. General regularities were revealed after injection of the experimental preparations. So, B. abortus TE in L- and S-form caused the immune response that increased granulocyte number and expression of early activation marker CD69 by T- and B-lymphocytes of blood in early period of observation (1-3 days), decrease in general B-lymphocyte content in late periods of observation (7-21 days). Thus, mice received B. abortus ТE in L-form demonstrated authentically higher CD69 expression of blood lymphocyte subpopulations than mice received B. abortus ТE in S-form. Distinctions in formation of humoral immune response were revealed that probably was connected with alteration of Brucella chemical composition in the course of L-transformation. Conclusion. The investigation established that B. abortus TE in L- or S-form caused immunological reorganization in the experimental animal organisms. On the basis of the fin

Background . Plague is a dangerous natural-focal bacterial disease that can cause emergencies of interstate significance. In 2014–2016, three bubonic plague cases were registered among local residents in the Republic Altai. This circumstance was the reason for implementation of complex preventive measures. Comprehensive studies of the immune status of humans vaccinated (revaccinated) with live plague vaccine are presented in this paper. These people constantly reside and work at the territory of Gorno-Altai  high-mountain natural plague focus. Methodology . The study of the clinical material (blood) from 60 volunteers included the determination of the functional activity of phagocytic cells, the production of IFN- γ , IL-4 and TNF- α cytokines, the titre of specific IgG anti-bodies to the capsular antigen of the plague microbe and the concentrations of the main classes of immunoglobulins in blood serum by enzyme immunoassay,  as well as immunophenotyping  of blood lymphocytes through flow cytometry and the de-termination  of the alleles of HLA class II genes by a polymerase chain reaction. Results . The materials of these studies made it possible to determine a number of important parameters indicative of the cellular and humoral immunity activation in humans immunized against plague. Frequently occurring alleles of the HLA-DRB1, HLA-DQB1 and HLA-DQA1 genes were defined. Possible associations of these alleles with the levels of TNF- α and IL-4 production, as well as with the relative content of T-helpers  and CD3-CD16+ cells were revealed. Conclusions . The obtained results indicate the immune reconstruction of the humans immunized against the plague. The immunological efficiency and safety of live plague vaccine were confirmed during the exacerbation of the epidemiological situation in active natural plague focus. Nevertheless, further immunological monitoring is necessary to fully characterize the immunological reactivity of the humans vaccinated (revaccinated) with live plague vaccine, and to improve the strategy for specific plague prevention in natural foci.

Background. Plague is an especially dangerous natural focal infectious disease belonging to a group of quarantine infections. There are eleven natural plague foci in Russian Federation. In Republic Tyva plague endemic territories include Ovyur, Mongun-Taigin and Tes-Hem areas where Y. pestis strains are intermittently isolated from Citellus undulates. Population living at the territory of the natural foci get immunoprophylaxis against plague at complication of epizootic and epidemic conditions.This paper presents the results of monitoring indicators of the immune status of people vaccinated with the plague vaccine living in the territory of the Tuva natural focus.Materials and methods. The study involved 76 volunteers who had not previously been vaccinated. The study included the determination of production IFN-γ, IL-4, TNF-α by blood cells, titers of specific IgG antibodies to the capsule F1 antigen of the Yersinia pestis, and concentrations of immunoglobulins in serum blood, as well as immunophenotyping of blood lymphocytes.Results. In the course of a comprehensive immunological study, features of the development of cellular and humoral reactions in people living in the territory of the Tuva natural plague focus were established in the first months after vaccination. Changes in the concentration dynamics of the main classes of immunoglobulins were accompanied by an increase in the level of specific IgGs to the F1 within 6 months after immunization. In the same period, a significant increase in the production of cytokines, as well as significant changes in terms of the subpopulation composition of the vaccinated blood.Conclusion. It is necessary to note the importance of studying of the human immune status in 1–3 months after plague vaccination as this period coincides with potentially dangerous season from epidemiological point of view. Nevertheless, much important role for improvement of tactics of the specific prevention measures plays the data received after the revaccination.

Introduction. The current direction in medicine is the creation of immunobiological preparations to increase the effectiveness of specific immunotherapy and immunoprophylaxis, containing immunomodulators in their composition. These natural or synthetic substances can have a regulating effect on the immune system. At present, water-soluble organic-inorganic polymeric materials with nanoparticles of various chemical substances with bactericidal and immunomodulating properties can serve as such promising compounds.The aimof the work is to study the acute toxicity of polymer nanocomposites based on 1-vinil-1,2,4-triazole copolymer with N-vinylpyrrolidone with silver, gold and selenium nanoparticles and their effect on the functional state of immune system cells in vitro.Materials and methods.The study of acute toxicity was performed on outbred white mice. The activity of superoxide dismutase and glucose-6-phosphate dehydrogenase were studied in guinea pig peritoneal macrophages. The study of spontaneous and nanocomposite-induced production of pro- (interferon gamma and tumor necrosis factor alpha) and anti-inflammatory (interleukin-4) cytokines by blood cells was carried out using clinical material obtained from volunteers using the ELISA method. Results. It has been established that nanocomposites with silver and gold nanoparticles do not cause the death of white mice, their temperature increase and body weight decrease. The average lethal dose for a nanocomposite with selenium nanoparticles was determined as 1 gram per 1 kilogram of animal mass. It was shown that the tested nanocomposites have a stimulating effect on the production of cytokines by human blood cells in vitro. It was established that a nanocomposite with selenium nanoparticles increases the activity of superoxide dismutase and glucose-6-phosphate dehydrogenase. A comparative analysis of their actions with the actions of commercial preparations of biological origin, with immunomodulatory properties.Conclusion. The data obtained allow us to substantiate the need for further research on the effects of nanocomposites based on 1-vinyl-1,2,4-triazole copolymer with N-vinylpyrrolidone with silver, gold and selenium nanoparticles on the macroorganism in both in vitro and in vivo conditions.

Aim . To study the subpopulational structure of blood cells of the experimental animals immunized with thermoextracts (TE) of Brucella abortus in L- and S-form. Materials and methods . Total 100 certified («Vector», Novosibirsk) outbred mice were immunized with B. abortus I-206 TE in L- and S-form in 20 μg protein dose. After 1, 3, 7, 14 and 21 days of observation the phenotypes (CD45, CD3, CD4, CD8, CD19, CD69) of blood cells were detected. Results . General regularities were revealed after injection of the experimental preparations. So, B. abortus TE in L- and S-form caused the immune response that increased granulocyte number and expression of early activation marker CD69 by T- and B-lymphocytes of blood in early period of observation (1-3 days), decrease in general B-lymphocyte content in late periods of observation (7-21 days). Thus, mice received B. abortus ТE in L-form demonstrated authentically higher CD69 expression of blood lymphocyte subpopulations than mice received B. abortus ТE in S-form. Distinctions in formation of humoral immune response were revealed that probably was connected with alteration of Brucella chemical composition in the course of L-transformation. Conclusion . The investigation established that B. abortus TE in L- or S-form caused immunological reorganization in the experimental animal organisms. On the basis of the fin

Background. Plague is a dangerous natural-focal bacterial disease that can cause emergencies of interstate significance. In 2014–2016, three bubonic plague cases were registered among local residents in the Republic Altai. This circumstance was the reason for implementation of complex preventive measures. Comprehensive studies of the immune status of humans vaccinated (revaccinated) with live plague vaccine are presented in this paper. These people constantly reside and work at the territory of Gorno-Altai high-mountain natural plague focus. Methodology. The study of the clinical material (blood) from 60 volunteers included the determination of the functional activity of phagocytic cells, the production of IFN-γ, IL-4 and TNF-α cytokines, the titre of specific IgG anti-bodies to the capsular antigen of the plague microbe and the concentrations of the main classes of immunoglobulins in blood serum by enzyme immunoassay, as well as immunophenotyping of blood lymphocytes through flow cytometry and the de-termination of the alleles of HLA class II genes by a polymerase chain reaction. Results. The materials of these studies made it possible to determine a number of important parameters indicative of the cellular and humoral immunity activation in humans immunized against plague. Frequently occurring alleles of the HLA-DRB1, HLA-DQB1 and HLA-DQA1 genes were defined. Possible associations of these alleles with the levels of TNF-α and IL-4 production, as well as with the relative content of T-helpers and CD3-CD16+ cells were revealed. Conclusions. The obtained results indicate the immune reconstruction of the humans immunized against the plague. The immunological efficiency and safety of live plague vaccine were confirmed during the exacerbation of the epidemiological situation in active natural plague focus. Nevertheless, further immunological monitoring is necessary to fully characterize the immunological reactivity of the humans vaccinated (revaccinated) with live plague vaccine, and to improve the strategy for specific plague prevention in natural foci.

The article covers the issues related to the scientific substantiation and methodological support of immunological monitoring of persons vaccinated against plague upon epidemic indications. The problematic issues of the methodology for the assessment of immunological efficiency (efficacy) of plague live vaccine (PLV) are noted. The current tasks and possible prospects for the introduction of immunological monitoring of persons vaccinated against plague upon epidemic indications have been defined. The algorithm of efficacy estimation of plague live vaccine in vaccinated (revaccinated) persons has been tested under real conditions. Analysis of the results of efficacy evaluation of plague live vaccine among vaccinated (revaccinated) people against plague living in the territories of natural foci of this infection has been performed. Demonstrated is the possibility of using immunological monitoring results in creating an objective basis for improving the strategy of specific plague prevention in natural foci of this infection. The priority areas for further optimization of the specific plague prevention in the territories of natural foci of the infection, including those related to the formation of individual regimen revaccination tactics, taking into account the possibilities of creating modern and effective vaccines, are outlined.