Natural killer cells (NK cells) represent a group of lymphocytes of innate immunity. In addition to NK cells of peripheral blood, tissue-resident populations are described. NK cells of the decidual envelope (decidual NK cells) represent one of the local NK cell populations. Decidual NK cells differ in phenotype and function from peripheral blood NK cells. These cells have, mainly, regulatory functions. At the same time they retain the ability to perform cytotoxic effects. In the uterus, NK cells are located closely to the cells of fetal origin, i.e., trophoblast cells, which differentiate from the outer layer of the invading blastocyst. The purpose of the review article was to analyze the literature data on the studies of the molecular interactions between NK cells and trophoblast cells, as well as potential means of regulating these interactions. The review presents currently available data on receptor-mediated effects (due to adhesion molecules and cytotoxic receptors) and distant interactions (involving cytokines, chemokines and growth factors secreted by the both cell types) between NK population and trophoblast cells. The receptors regulating contacts of NK cells and trophoblast cells with extracellular matrix are also considered. The review provides information on activation of signaling pathways in NK cells and trophoblast cells resulting from their interaction with each other and components of the extracellular matrix. Currently, the molecular mechanisms regulating the NK cell functions and their interaction with trophoblast cells have not been studied sufficiently. The authors attempted to consider molecular regulation of the functional activity of NK cells mediated by the molecular complex of RNA polymerase II. We also describe participation of cyclin-dependent CDK8/19 kinases which comprise a part of the mediator complex which provides functioning of immune cells. The data on the participation of CDK8/19 in regulation of intracellular signaling pathways, as well as influence of CDK8/19 on the NK cell functions, are considered. Summarizing the data presented in the literature, one may emphasize that there is an extensive mutual influence of NK cells and trophoblast cells in decidual lining of uterus during pregnancy, thus leading to a changes in phenotype and functions of these cells. Experimental studies are required on the contribution of molecular mechanisms involved in transcription and translation processes to the biology of NK cells, and their role in maintaining interactions between NK cells and trophoblast cells, including the pathways involving CDK8/19.

Conflicting data on the role of the metabolic syndrome (MS) in the development of hepatocellular carcinoma (HCC) require studies on the influence of molecular factors that are important in the development of HCC in MS, which was the goal of our review. Publications (scientific articles and reviews) over the past 10 years were studied and analyzed using the databases Web of Science, Scopus, PubMed, RSCI. The terms used for the search were “metabolic syndrome and non-alcoholic fatty liver disease”, “metabolic syndrome and non-alcoholic steatohepatitis”, “metabolic syndrome and hepatocellular carcinoma”. The total number of publications studied in all databases exceeded 570 units, while the review presents the most significant results at the present stage. Insulin resistance and obesity, through the development of a systemic chronic inflammatory state, lead to increased inflammation and fibrosis in the liver, which are prodromal signs of hepatocarcinogenesis, increase the production of insulin-like growth factor-1 and disrupt the regulation of the insulin-like growth factor pathway. People with HCC have been shown to overexpress IGF-2. IGF-binding proteins, due to the reduced bioavailability of free IGF-1 and IGF-2 in the circulation, are able to inhibit the growth of HCC. In MS, a pro-inflammatory state is detected, which is caused by the production of cytokines by adipocytes (IL-6, IL-8, IL-1β, tumor necrosis factor α (TNFα), VEGF and chemokine ligands 2 and 5), which recruit immune cells, promoting angiogenesis and enhancing chronic inflammation. Transcription factors (PPAR) are involved in hepatocarcinogenesis, the significance of different factors is not fully understood. Leptin has a positive prognostic value in HCC, improving overall survival, and visfatin has a negative effect on hepatocarcinogenesis. Activation of PAI-1 inhibits the progression of HCC through PPARγ stimulation. Adiponectin may be a prognostic marker in HCC, with a lower serum concentration positively correlated with worse prognosis.

Cellular homeostasis in the body is known to be maintained by the processes of cell proliferation and death, whereas apoptosis is the most frequent and physiological, “silent” mechanism of cell elimination. It has been currently shown that the process of apoptosis traditionally considered an autonomous event, has a pronounced non-autonomous effect on migration, proliferation, and death of the neighboring cells. This work was based on the data on impaired programmed death of mononuclear cells from the patients with rheumatoid arthritis (RA) leading to the evolving autoimmune inflammation. The aim of this study was to evaluate effector molecules exerting autonomous and non-autonomous influence of T cell apoptosis under the conditions of “cell neighborhood” in cell cultures of healthy people and RA patients. The studies were performed with blood samples of RA patients and healthy women of comparable age. These experiments were performed in order to assess the levels of main molecules mediating the in vitro receptor and mitochondrial apoptosis of T lymphocytes. In previous studies, using the original “cell neighborhood” model, no differences were found in parameters of early and late activation apoptosis between the groups of donors and RA patients. At the same time, 1-week incubation in apoptotic cultures of the patients was followed by significantly increased number of viable cells carrying the proliferation marker Ki-67. Different results of in vitro apoptosis induction in cultures under similar conditions of “cell neighborhood” in healthy people and patients with RA have revealed the importance of main effector molecules of apoptosis in the studied groups. In this study, we have revealed low potential of the receptor pathway for apoptosis activation in healthy people, due to suppression of TNFα production during cell incubation under the conditions of “cell neighborhood”, and in RA patients due to initially low TNFα in supernatants which did not change over time and in various incubation variants, along with low content of initiating caspase 8 in both groups. Significant suppression of effector molecules of mitochondrial pathway of apoptosis activation, i.e., Bcl-2 anti-apoptotic factor and p53 transcription factor was detected in cultures of apoptotic cells, as well as mixtures of proliferating and apoptotic cells under the conditions of “cell neighborhood” in RA patients. The amounts of these molecules did not change in healthy persons. At the same time, no differences in these molecules were found between individual variants of cell cultures from the patients with RA and healthy people. The both studied groups were characterized by a significant activation of IL-4 and IL-6 production, i.e., the cytokines with autonomous and non-autonomous protective and reparative properties, Hence, one may conclude that high levels of these cytokines had different effects in cell cultures under the conditions of “cell neighborhood”. Incubation of cells from healthy people under suboptimal conditions was associated with maintaining the balance of proliferation and apoptosis, whereas, in cell cultures of RA patients, this balance caused activation of proliferation processes, being accompanied by an increase in the number of living cells in apoptotic cultures.

Formyl peptide receptors (FPRs) are an important part of innate immunity involved in antimicrobial phagocyte functions such as chemotaxis, secretory degranulation, and respiratory burst. These phagocyte responses are observed in both acute and systemic chronic inflammation. Abundant or constant release of pro-inflammatory ligands leads to the pre-activation of phagocytes when subsequent stimulation induces more intense cellular response. Binding of the formyl peptide receptor with its agonist activates production of reactive oxygen species, due to triggering phosphorylation of the cytoplasmic subunits p47phox and p67phox followed by their translocation to the plasma membrane and assembly into the NADPH oxidase complex. Rheumatoid arthritis is characterized by an imbalance of immune processes and autoimmune responses against the own joint tissues. It is known that, granulocytes produce increased amounts of oxygen radicals in various pathologies, including rheumatoid arthritis. We suggest that such enhancement may be due to increased expression of formyl peptide receptors or components of the FPR/PKC/NOX2 signaling pathway. Our aim was to study the mRNA expression of fpr1/fpr2 genes and the FPR-dependent production of reactive oxygen species by isolated peripheral blood granulocytes from the patients with rheumatoid arthritis. Materials and methods. The objects of the study were isolated peripheral blood granulocytes. We analyzed, respectively, 166 and 85 samples from the patients with rheumatoid arthritis and healthy donors. The production of reactive oxygen species was assessed using luminol-dependent chemiluminescence. For FPR1 activation we used a distinct concentration of the formyl peptide fMLF: the response to it was completely inhibited by pretreatment of the cells with FPR1 antagonist N-t-boc-MLF. FPR2 activation was performed by synthetic peptide WKYMVM, a specific receptor agonist. In the patients with rheumatoid arthritis, we have revealed an increased level of spontaneous and phorbol ester-induced production of reactive oxygen species by isolated peripheral blood granulocytes, thus reflecting a pre-activated state of the phagocytes in rheumatoid arthritis. We have found the increased FPR1-mediated production of oxygen radicals and expression of mRNA of fpr1 gene in blood granulocytes of rheumatoid arthritis patients. Furthermore, the enhancement of oxidase function may be associated with constitutive activation of the FPR1/PKC/NOX2 pathway as shown by positive correlation between the processes. The production of reactive oxygen species induced by stimulation of the FPR2 receptor is also increased, but it cannot be directly attributed to overexpression of the receptor mRNA or PKC/NOX2 activation, and requires further study. Understanding the mechanisms of regulation of the FPR1 and FPR2 signaling cascades may reveal new targets for anti-rheumatoid therapy.

In humans circulating monocytes include classical (CD14⁺⁺CD16^- ), intermediate (CD14⁺⁺CD16⁺) and non-classical/alternative (CD14⁺CD16⁺⁺) monocytes, which in turn can be activated via the classical or alternative pathway. Pregnancy is accompanied by significant changes in the monocyte compartment, which is manifested by an increase in the number of circulating monocytes, including the proportion of intermediate monocytes, and a change in their function. However, the functional properties of monocyte subsets during gestation remain largely unexplored. We hypothesized that circulating monocytes may be activated in an alternative pattern and acquire features of M2 polarization (anti-inflammatory / immunosuppressive properties). The aim of the investigation was to study M2-associated markers that characterize the anti-inflammatory and immunosuppressive potential of myeloid cells in subpopulations of circulating monocytes in fertile nonpregnant women and women with uncomplicated pregnancy in the 2nd trimester. It was shown that in fertile non-pregnant women intermediate and non-classical monocytes are characterized by a higher expression of M2-associated markers (CD206, Arginase 1, MerTK) compared to classical monocytes. In the 2^nd trimester of pregnancy, the expression of these molecules on monocytes increases significantly, which is manifested by 1) an increase in the proportion of CD206⁺ cells in subpopulations of classical and intermediate monocytes, 2) an increase in the mean fluorescence intensity of Arginase 1 in all monocyte subsets, 3) an increase in the proportion of MerTK⁺ cells in subpopulations of classical and intermediate monocytes and mean fluorescence intensity across all monocyte subsets. The highest content of CD206⁺ and MerTK⁺ cells in pregnant women is detected in the subpopulation of intermediate monocytes, and the highest values of the mean fluorescence intensity of Arginase 1 and MerTK – in the subpopulations of intermediate and non-classical monocytes. The data obtained demonstrate that monocytes of pregnant women in the 2nd trimester of pregnancy are characterized by signs of M2 polarization. This is confirmed not only by an increase in the expression of the M2-associated mannose receptor CD206, but also by an increase in the expression of Arginase 1 and MerTK, which mediate the immunosuppressive activity of myeloid cells and, in particular, macrophages of the M2 phenotype. Further studies of M2-associated markers in monocyte subpopulations during gestation will allow a more detailed characterization of the regulatory role of circulating myeloid cells during pregnancy. 

IL-17A is a proinflammatory cytokine involved in pathogenesis of some neuroinflammatory diseases of the brain. However, its role in schizophrenia is poorly understood. Currently, noninvasive neuroimaging techniques are widely used to assess abnormalities in brain morphology and interactions of neuronal networks in schizophrenia. The aim of this work was to study associations between IL-17A level and brain morphometric parameters in schizophrenia, in order to clarify immune factors of pathogenesis and search for biomarkers of unfavorable disease course. 45 patients with schizophrenia and 30 healthy volunteers were included into the study. The levels of cytokines (IL-5, IL-6, IL-8, IL-10, IL-17A) and inflammatory markers were determined by ELISA or multiplex analysis. MRI scans were performed with a Siemens Magnetom Verio 3T MRI scanner. We used Kruskal–Wallis test to assess significant differences in immunological parameters followed by Mann–Whitney paired comparison; Student test to assess the significance of differences in morphometric parameters of the brain; Fisher exact test to assess the differences in discrete variables, with the differences considered statistically significant at p < 0.05. IL-17A levels were found to be increased in schizophrenia. Its elevated content was associated with increased levels of C-reactive protein, IL-5, IL-6, IL-8, IL-10, and the presence of morphometric changes of frontal and temporal cortex in the patients. So far, the relationships between IL-17A levels, immunoinflammatory parameters and structural brain changes have not been studied in schizophrenia. In the present work, we found an association of elevated IL-17A levels with decreased cortical thickness in several brain regions, systemic inflammation and activation of Th2-link of adaptive immunity in the patients with schizophrenia. According to the literature, a number of brain areas, where cortical thickness was associated with IL-17A levels may be relevant to pathogenesis of the disease and, in particular, to the development of negative symptoms, including impoverishment of interests, speech, and emotions. The results are important for understanding the role of immune disorders in pathogenesis of schizophrenia, including structural changes of the brain, and suggest that IL-17A may be a biomarker of these disorders. Confirmation of associations between structural neuroimaging findings, laboratory markers of inflammation and immune disorders may provide the basis for new multidisciplinary approaches to the diagnosis and prognosis of schizophrenia.

Systemic immunological disorders are associated with various geriatric conditions, including cognitive dysfunction. However, in patients with diabetic retinopathy, the changes of blood interleukin profile were studied without considering the severity of cognitive impairment. The aim of this study was to analyze blood plasma levels and intercorrelations of interleukins in the patients with diabetic retinopathy accompanied by mild and moderate cognitive impairment. Fifty-four elderly patients with diabetic retinopathy and mild cognitive impairment, and 62 patients with diabetic retinopathy and moderate cognitive disorders underwent inpatient examination and treatment at the Tambov branch of the S. Fedorov Center of Eye Microsurgery over 2021-2022. The interleukins contents in blood plasma were studied by enzyme immunoassay using the Protein Contour kit, including IL-1α, IL-1β, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-10, IL-12, IL-17, IL-18. The diagnostics of diabetic retinopathy was based on comprehensive ophthalmological examination, according to the Clinical recommendations of the Society of the Russian Association of Ophthalmologists «Diabetes mellitus: diabetic retinopathy, diabetic macular edema». Cognitive functions were assessed according to a valid Mini- Mental-State-Examination scale. It has been shown that the patients with diabetic retinopathy and moderate cognitive impairment have a significantly increased level of all the studied proinflammatory interleukins, as compared to similar cohort with diabetic retinopathy accompanied by a mild cognitive impairment. In mild cognitive disorders, the content of IL-6 in blood plasma was higher (24.4±2.1 pg/mL versus 5.1±0.8 pg/mL, p < 0.001). Development of moderate cognitive impairment in the patients with diabetic retinopathy was also accompanied by a statistically significant increase of plasma IL-8 to 36.7±3.5 pg/mL versus 10.5±2.3 pg/mL with mild cognitive impairment; IL-17, to 21.9±1.8 pg/mL versus 8.5±1.1 pg/mL, respectively. Concentrations of anti-inflammatory interleukins in blood plasma of the patients with diabetic retinopathy and moderate cognitive dysfunction were significantly decreased, i.e., IL-4 to 2.1±0.3 pg/mL versus 3.4±0.5 pg/mL in cases of mild mental deterioration; IL-10, to 8.7±0.5 pg/mL versus 15.4±1.3 pg/mL, respectively. A sufficient correlation was shown between the levels of systemic interleukins and moderate cognitive disorders in the patients with diabetic retinopathy. For the proinflammatory interleukins in cases of moderate cognitive impairment, an inverse correlations with IL-1β (r = -0.336; p = 0.021), IL-6 (r = -0.584; p = 0.019), IL-8 (r = -0.469; p = 0.006), and with IL-17 (r = -0.348; p = 0.018) were shown. The content of IL-4 and IL-10 in blood plasma of the patients with diabetic retinopathy correlated with moderate cognitive impairment at a significant level of r = +0,407 (p = 0.016) and r = +0.359 (p = 0.008), respectively. In mild cognitive impairment, the correlations with fewer numbers of interleukins were revealed, i.e., IL-1β, IL-6, IL-8 and IL-10, and exhibit weaker connections, except of IL-6 (a moderate connection level). Development of moderate cognitive impairment among the patients with diabetic retinopathy may be caused by increase in IL-1β, IL-6, IL-8, IL-17, and a decrease in IL-10. 

Respiratory allergy takes a significant place among allergic diseases. Similar clinical manifestations occur in sensitized patients in response to various airborne allergens. Accordingly, the allergen testing by means of in vivo and in vitro techniques is necessary to identify a causally significant allergen. The main laboratory assay to estimate sensitization to the airborne allergens is based on detection of specific immunoglobulin E (sIgE). However, clinical manifestations cannot be always confirmed by this test. The aim of this work was to evaluate the potential of basophil activation test (BAT) using flow cytometry, in order to confirm sensitization to house dust mite allergens. The BAT was carried out with allergens from Dermatofagoides in 34 volunteers, 130 patients were examined at the Russian Centre of Emergency and Radiation Medicine (33 people with household and 97 people with polysensitization), and 10 patients with allergy to house dust mites confirmed by skin testing. The sensitization was assessed using two laboratory kits (Allergenicity and BD FastImmune). The total IgE and sIgE to house dust mites, as well as concentrations of eosinophilic cationic protein, were determined. Specificity of the BAT with Allergenicity kit for the house dust mites was 94%. The sensitivity was 88% in the patients with household sensitization, thus being comparable with skin testing results available from the literature. An absolute correlation was found between positive results of skin testing and the BAT. In patients with household sensitization, sIgE levels > 0.35 UA/mL were detected in 39% of cases. A positive correlation was shown between the indices of basophil activation in response to testing allergens, and total immunoglobulin E and sIgE concentrations. High degree of correlation was found between the results of Dermatofagoides sensitization testing with both BAT kits. It was shown that the use of H1 histamine receptor blockers had no effect on BAT results. A decrease in sensitivity assay for airborne allergens was revealed upon therapy with glucocorticosteroids. Due to the proven clinical significance of the basophil activation test for diagnosing sensitization to inhaled allergens, one may require to supplement the range of approved assays in Russian Clinical Guidelines with BAT testing to prove sensitization in patients with allergic rhinitis and bronchial asthma, thus contributing to better diagnosis of causally significant allergens and, accordingly, administration of proper therapy.

In view of increased incidence of IgE-mediated diseases in Russia and worldwide, the efforts of various research groups are focused on studying the mechanisms that trigger the process of switching B-lymphocytes to IgE synthesis upon human exposure to harmless allergens, including the role of various antigen-presenting cells (APCs) in this process. However, the role of distinct APCs upon long-term penetration of low antigen doses via the tissue barriers, is yet poorly understood, as well as specific features of these events upon entrance of the antigen through the subcutaneous adipose tissue which contains tissueassociated lymphoid clusters (TALC).The aim of this work was to determine the relationship between the local accumulation of various APCs in the subcutaneous adipose tissue and development of early IgE production in a clinically relevant experimental model of allergy with long-term administration of low allergen doses. In this experimental model, specific IgE synthesis is induced, with minimal concomitant IgG production, thus mimicking the situation observed in patients with clinically sound allergies. BALB/c mice were immunized for 4 weeks subcutaneously in the withers area or intraperitoneally with low (100 ng) or high (10 μg) doses of the model allergen (ovalbumin). Blood samples were taken weekly from mice for ELISA testing, to determine the production of specific antibodies. Provocation tests were performed with high dose of the allergen, and adipose tissue samples were taken from the site of antigen injection for flow cytometric assays, in order to evaluate the contents of various APC subpopulations. Specific IgE production was induced mainly by subcutaneous injection of the antigen at low doses (100 ng) into the area of withers. When using this experimental regimen, we observed accumulation of classical CD11b⁺ cells in adipose tissue at the withers site, but not in the peritoneal adipose tissue, in absence of CD11b^- classical, inflammatory or plasmacytoid, dendritic cells. These findings coincided in time with increased production of specific IgE on days +14 to +21. Accumulation of CD11b⁺CD11c^- macrophages and their CD206⁺ M2 subpopulations at early terms (days +7 and +21) was also observed only after subcutaneous injection of the antigen into the withers area. The high-dose antigen injection (10 μg) which mediated IgG₁ production to greater extent than production of IgE, led to earlier accumulation of CD11b⁺ classical dendritic cells (on day 7^th), and to the absence of macrophage accumulation at later stages (day 21^th). Thus, the early start of specific IgE production upon low-dose injection of the antigen into the subcutaneous adipose tissue may be associated with its presentation by CD11b⁺ classical dendritic cells in the presence of CD11b⁺CD11c^- macrophages.

The aim of present study was to establish the relationship between the level of blood serum cytokines and indexes of pulmonary function as well as to identify the markers of evolving dysfunction of small airways in obese patients with partially controlled mild bronchial asthma. We have examined 53 patients with mild asthma of partially controlled clinical course complicated with obesity (I-II degree). The control group consisted of 25 healthy volunteers. All participants underwent spirometry, bodyplethysmography. Tumor necrosis factor alpha (TNFα), interferon gamma (IFNγ), interleukins (IL) IL2, IL-4, IL-6, IL-10, IL-17A were determined in blood serum. In the patients with partially controlled mild asthma, an increase in IL-17A by 55.8%, and IL-4 by 44.9% was detected, regardless of body mass. According to the results of cluster analysis, two sub-groups were discerned, depending on the state of the small airways and the levels of pro- and anti-inflammatory cytokines. The dysfunction of small airways was shown to be accompanied by hypercytokinemia being more common in bronchial asthma with predominant Th1-and Th17-immune responses. We have revealed an association between IL-17A, IL-6 levels and functional indices reflecting the state of the small airways, as well as correlation between IFNγ and the indices of bronchial obstruction. The features of pulmonary function were found to be dependent on the cytokine status in mild asthma with obesity. Two immuno-functional variants were identified, differing in activity of systemic inflammation, type of immune response, and functional state of the small airways. The revealed relationships allow us to consider IL-17A, IL-6 and IFNγ as markers of small airways dysfunction in mild asthma of partially controlled clinical course associated with obesity.

The purpose of the present work was to evaluate population immunity to influenza and molecular genetic analysis of influenza viruses detected in the Russian Federation over 2020-2022. In this study, 1344 samples of blood serum collected prior to the 2021-2022 flu season in Siberian, Southern, Far Eastern, Volga and Ural Federal Districts were studied. Seropositivity to the A/Victoria/2570/2019 vaccine strain (H1N1) pdm09 was detected in 25% to 31% of samples from the four federal districts, and in 8% of samples from the Far Eastern Federal District. Seropositivity to the A/Cambodia/e0826360/2020 strain (H3N2) was detected in 24% to 37% of the samples. The lowest population immunity was revealed to the influenza B/Washington/02/2019 vaccine strain (Victoria lineage), with < 10% of serum samples reactive to the studied strain. Since March 2020, the worldwide turnover of all seasonal respiratory viruses has sharply decreased, except of rhinoviruses. From March 2020 to June 2021, we have identified six B/Victoria influenza viruses from sporadic cases of influenza. From June 2021 to the end February 2022, the State Research Center “Vector” received 901 samples positive for influenza A(H3N2) virus RNA, two specimens positive for A(H1N1) pdm09 virus RNA, and 17 samples positive for influenza B. All studied A(H3N2) viruses belonged to the 3C.2a1b.2a2 subclade (Bangladesh group). The two verified A(H1N1) pdm09 influenza viruses belonged to the 6B.1A.5a clade. All studied influenza B viruses were assigned to the B/Victoria genetic lineage, and to 1A.3a2 subclade. The genomes of all identified viruses did not contain mutations of the NA gene responsible for drug resistance to neuraminidase inhibitors, or mutations in РA gene responsible for baloxavir resistance. All viruses tested by fluorescence assay were sensitive to oseltamivir and zanamivir. The worldwide frequency of influenza isolates resistant to antineuraminidase drugs does not exceed 1-2% of cases. Hence, oseltamivir and zanamivir provide effective treatment for seasonal influenza.

Increasing attention is being paid to methods for detecting primary and secondary T and/or B cell immunodeficiencies. Their implementation into laboratory diagnostics would contribute to the early diagnostics of immunodeficiencies. Currently, the number of identified adult patients with immunodeficiencies of various origins is steadily increasing. Age, gender and ethnicity of patients may be significant factors of immunity. Hence, determination of the population reference intervals for TREC and KREC DNA excision rings in peripheral blood of adult persons is an urgent laboratory task for in-depth examination of both congenital and acquired immunodeficiency conditions. Our purpose was to determine the reference intervals for the quantitative assay of TREC and KREC fragments in peripheral blood among the adult population of St. Petersburg. We studied whole blood samples obtained from 717 apparently healthy volunteers aged 18 to 108 years within the program of population immunity assessment among residents of St. Petersburg. The exclusion criterion included immunodeficiency of any origin, viral hepatitis A, B, C, HIV infection. Quantitation of the target TREC and KREC DNA fragments was carried out using a set of reagents for the quantitative determination of excisional rings TREC and KREC by Real-time PCR (TREC/KREC-AMP PS). The reference intervals were determined by the direct method according to the recommendations of the International Federation of Clinical Chemistry and the Russian State Standard (GOST) R 53022.3-2008. The volunteers were divided into six age groups: 18-29, 30-39, 40-49, 50-59, 60-69 years old, and the persons over 70. The amounts of TREC and KREC in each blood sample were determined for all age groups. Upon correlation analysis, we have revealed a negative relationship between the concentration of TREC molecules in blood samples, and the age of study participants (Spearman correlation coefficient r = -0.80 (p-value < 0.0001)). Significant differences in TREC levels between different age groups were revealed. No correlations were detected between KREC contents in blood samples and age as well as any differences between age groups. Reference intervals of the TREC level were determined for each mentioned age group. A unified reference range was established for the KREC levels. The established reference intervals for TREC and KREC molecules in adults are significantly lower than in newborns. The obtained results enable determination of reference intervals for TREC and KREC levels among adults, thus contributing to effective personalized laboratory diagnosis of immunodeficiency states of various origins.

Chronic inflammation in obstructive pulmonary disease develops in genetically predisposed individuals with prolonged or massive exposure to allergens or toxic air pollutants. This effect leads to hyperactivation of immune system and development of uncontrolled inflammatory response. The aim of the study was to determine the level of cytokines in the supernatant of leukocytes from the patients with COPD and asthma following incubation with air toxicants, i.e., a solution of cigarette smoke, an extract of cigarette tobacco, or a solution of exhaust combustion gases. The cytokines were determined by ELISA in the supernatants following exposure of peripheral venous blood leukocytes to the toxicants. To perform the assays, 10-mL samples of peripheral venous blood from the patients were taken into the test tubes with heparin (20 U/mL) in the morning time, not earlier than 2 days after therapeutic infusions of glucocorticosteroids. After gravity sedimentation, the leukocyte-rich was removed, centrifuged at 1500 rpm, then the liquid was discarded, and the leukocyte pellets were diluted with buffered saline (2 106 cells/mL). Individual leukocyte suspensions were divided into 4 wells of an immunological plate, 100 μL each. Equal volumes of test solutions simulating the effect of toxicants were added to three wells. The fourth well contained sterile isotonic sodium chloride solution (negative control). The mixtures in plates were exposed for 45 min at 37 °C followed by centrifugation for 10 min at 1500 rpm. From each well, 50 μL of the supernatant was taken and transferred to the plate for ELISA assays (under the same number). As a result, we have found that the solutions of cigarette smoke and exhaust gases caused release of IL-1β by leukocytes in the patients with asthma and COPD, but not in the samples from control group of healthy volunteers. Spontaneous increase in the IL-1β level was registered in the patients with asthma. The cigarette extracts caused an increased release of TNFα in the supernatant fluid of the patients with COPD. Upon exposure to a solution of exhaust gases, an increased level of TGF-β was revealed in patients with asthma compared to spontaneous cell activation (p < 0.05), as well as an increase in IFNγ contents in the patients with COPD as compared with control group (p < 0.05). No statistically significant changes were revealed for the levels of IL-6, IL-2, IL-4, IL-12, IFNα upon exposure of air toxicants on the leukocytes of patients with COPD, asthma or healthy volunteers.

The results of recent studies demonstrating the presence of pro-inflammatory mediators in osteoarthritis (OA), as well as known similarity of histological signs of inflammation in rheumatoid arthritis (RA) and OA, suggest an important role of NETosis in immune inflammation in OA patients. Our objective was to assess ability of blood neutrophils from ОA patients to generate NETosis spontaneously and after in vitro induction, and impact of reactive synovitis on the dynamics of NETosis indexes. Thirty-one patients with verified OA and 30 healthy volunteers were included into the study. Circulating neutrophils were isolated with one-step density gradient centrifugation using double layers of Iohexol gradient. Subpopulational profile of isolated neutrophil fractions, their viability, and nonspecific activation were evaluated microscopically using Trypan Blue exclusion test, as well as nitro-blue tetrazolium test. NETs were induced by phorbol-12-myristate13-acetate (PMA). Spontaneous and induced formation of NETs was assessed using fluorescence microscopy. The ОA patients were in clinical remission at the time of inclusion in the study. In 23 OA patients, an exacerbation was diagnosed during the study. The neutrophil fractions showed high purity and a high content of viable nonactivated cells. These parameters were comparable in the study groups. Mean percentage of spontaneous NETs in OA patients in remission was significantly increased comparing to healthy controls. Usage of PMA, as inducing agent was accompanied by a significant increase in ability of neutrophils to form NETs. Transition of OA to exacerbation was characterized by further significant increase in spontaneous and PMA-induced NETs. Spontaneous and induced NETs in OA patients at acute stage of the disease are significantly higher than in OA patients in remission state. The growth rate of spontaneous NET formation is 3.74 times higher than the induced NET formation in OA patients upon exacerbation. Statistically significant increase in the ability of peripheral neutrophils to spontaneous and induced formation of extracellular traps was found, depending on the stage of osteoarthritis. The data obtained suggest an opportunity for participation of circulating neutrophils via NETosis in pathogenesis of immune inflammation in OA.

Thromboembolic syndrome is the most dangerous complication of atrial fibrillation which develops in about 8-15% of cases, thus presuming the role of persisting left-heart thrombosis in presence of anticoagulant therapy in some patients. When activated, the blood platelets express multiple copies of CD40L on their membrane. Hence, the soluble form of CD40 ligand is considered a marker of platelet activation and pathogenic processes associated with increased activity of the thrombotic system. Our aim was to study the content of CD40, soluble CD40 ligand and thrombomodulin in the patients with atrial fibrillation of non-valvular genesis receiving anticoagulant therapy, discerning those with a history of thrombotic complications, and the cases with atrial fibrillation, however, free of thrombotic complications. The study group included 22 healthy volunteers and 60 patients diagnosed with atrial fibrillation who received anticoagulant therapy, of whom 21 patients have developed thrombotic complications in the course of adequate anticoagulant therapy. Quantitative assays of CD40, soluble CD40 ligand and soluble thrombomodulin were performed by enzyme immunoassay using Core Facility “Medical Genomics”, Tomsk National Research Medical Center. Concentration of soluble CD40 ligand in both groups of the patients with atrial fibrillation significantly exceeded appropriate values in the group of healthy volunteers. CD40L content was increased in the group of patients with thrombotic complications against the group of patients without thrombotic complications. Thrombomodulin content in blood serum was decreased in the patients with thrombotic complications, as compared to both thrombosis-free patients, and to practically healthy volunteers. The study of CD40/CD40L system and thrombomodulin showed that the patients with thrombotic complications exhibited higher serum level of soluble CD40L, with a simultaneous decrease of thrombomodulin, a physiological anticoagulant. A comparative analysis of the CD40/sCD40L system showed increased concentrations of the biomarkers in females, when compared to males.

We present a case of long-term organ functioning (ca.10 years) after allografting of a cadaveric kidney without usage of immunosuppressing drugs. In 2005, a patient suffering from a hypertensive form of chronic glomerulonephritis, have received an allogeneic graft of cadaveric kidney compatible for AB0 system, HLA antigens (A19, B07, DR04), and negative results of cross-match test. The graft function was immediately restored, with normalization of creatinine levels achieved 4-5 days after surgery. Immunosuppression with cyclosporine, solumedrol, cellсept, metypred and simulect was performed in the hospital. Pulse therapy with solumedrol was performed on the day +20 due to the development of initial rejection signs. The postoperative period proceeded without infectious complications. The patient was discharged being recommended to take cyclosporine, Cell-Sept and Metypred. Within a year after transplantation, the patient claimed for pain in the hip joint, and, therefore, metypred was completely canceled. Subsequently, the Cellcept was replaced with a Mayfortic. In 2007, the signs of coxarthrosis were revealed at computed tomography, followed by aseptic necrosis of the the right femur head. Deforming osteoarthritis of the right hip joint was detected, and the hip replacement surgery was suggested. In 2010, due to risk of side effects from ongoing immunosuppressive therapy, e.g., joint damage, the Mayfortic was canceled. In 2012, being in fear of original Sandimmun Neoral replacement by a generic drug, the patient completely refused cyclosporine therapy. In 2021, the endoprosthetics of the right hip joint was performed, and the surgical wound healed initially. Since 2012, the patient has not completely taken immunosuppressive therapy. Over this time period, the patient has never been admitted to the hospital for impaired functioning of the organ graft. Meanwhile, he monitored his graft function on regular basis undergoing biochemical analyses, clinical examination, ultrasound studies of the graft and made regular visits to the outpatient department. In 2021, a week after hip replacement, there was a slight increase in serum creatinine, followed by further increase to 230 mmol/L in 2021, and to 310 mmol/L in March 2022. In February 2022, the patient suffered mild respiratory infection (confirmed COVID-19). In March 2022, the first clinical signs of increasing nephropathy appeared, i.e., swelling of both lower extremities, with leukocytes in urine upon routine analysis, increased blood flow resistance in the main artery of the transplant shown by ultrasound study. Due to worsening of the patient’s condition, he resumed taking the prescribed immunosuppressants.