
In 1968, Coombs and Gell proposed a classification of allergic disorders based on then available knowledge in immunology. Four types of reactions were identified: type I , immediate (IgE-mediated); type II, cytotoxic (mediated by antibodies and Fc-receptors of cells); type III, mediated by immune complexes, and type IV, the delayed type (T-cell-mediated). This classification proved to cover pathogenesis of allergic disorders, but also the mechanisms of autoimmune, infectious and parasitic diseases. Rapid development of immunology at the edge of XX and XXI centuries has revealed many new patterns that required updating the classification. In 2023, the European Association of Allergists and Clinical Immunologists (EAACI) proposed its own classification. It included the first 3 types from the Coombs and Gell classification. Meanwhile, the type IV cell-mediated reactions were divided into 3 subtypes: type IVa - T1 (type Th1), IVb - T2 (type Th2), IVc - T3 (type Th17). In addition, 3 more types were added: type V, with alteration of epithelial barriers; type VI, metabolically induced immune dysregulation, and type VII, with direct inflammatory response to chemicals. Unfortunately, the EAACI2023 classification does not provide a complete pattern. It does not follow a single classification principle, relying on pathogenetic, etiological, or structural aspects. But the main drawback of this classification is that the authors continue to consider allergic diseases as a separate area, while there is nothing special about them. In fact, there is no specific mechanism seen in allergic diseases that could be, at least, somehow differ from the general immunological reactions. Moreover, all these mechanisms were formed in the course of evolution as protective mechanisms, and not as pathological ones. This article concerns modern concepts of immune response, specifying 6 types of immune reactions and 5 levels of their implementation. In addition, 5 types of effector mechanisms of immune reactions are considered, forming a complex multi-level network of immune protection. The need for knowledge of immunology by clinicians of any specialty for adequate usage of immunodiagnostics and immunotherapy with bioengineered drugs is highlighted.
Long-term sequelae of COVID-19 include disturbances in the immune and endocrine systems. Of particular interest is the role of cortisol as a key stress response hormone, potentially affecting restoration of immune homeostasis in patients with post-COVID syndrome. Altered regulation of the hypothalamic-pituitary-adrenal axis may form various immune phenotypes that complicate individual adaptation after infection. Our objective was to assess the parameters of immune response in patients with post-COVID syndrome depending on the blood cortisol level, emphasizing the indices on natural killers, T-lymphocytes and platelets. Materials and methods: We have examined 109 patients who had COVID-19 at least 6 months ago. Blood serum samples were collected in the morning time. Serum cortisol levels were measured in order to stratify patients into three groups: with normal, elevated and reduced values. Immune status of the patients was assessed by flow cytometry. The levels of NK cells, T lymphocytes and their subpopulations (helpers, cytotoxic cells) were analyzed both by CD45+ and CD46+ panleukocyte markers, as well as general blood test parameters, including the mean platelet volume. Statistical evaluation was performed by means of nonparametric methods. Results: Patients with low cortisol levels showed a significant reduction in both absolute and relative number of NK cells, as well as a decrease in the average platelet volume. In this group, an increased number of T lymphocytes was also observed. In patients with hypercortisolemia, a decreased level of T cytotoxic cells was recorded. The immune differences clearly correlated with individual cortisol levels. Conclusions: The obtained data demonstrate presence of at least two immune phenotypes in post-COVID patients: (1) a pattern associated with hypercortisolemia and decreased cytotoxic T cells; (2) phenotype with hypocortisolemia, NK cell deficiency and platelet activity. These differences suggest a need for taking the hormonal status into account when assessing and treating post-COVID conditions.
VEGF-A is significant cytokine associated with angiogenesis. In SARS-CoV-2 infection (COVID-19), an increased level of VEGF-A was detected in serum being associated with severity and mortality of the disease. A number of polymorphic sites have been identified in regulatory regions of this gene that are associated with VEGF production. The VEGF-2758 (rs699947) is located in promoter region of this gene and the VEGF-2578 CC genotype is associated with higher production rates. The VEGF 936 (rs3025039) is located at the 3' untranslated region of VEGF gene, and its T allele is associated with a reduced plasma protein level. The aim of the study was to analyze the association of polymorphic positions of the regulatory regions of the VEGF gene (rs699947 and rs3025039) with clinical severity of the disease and cardiovascular problems in patients from the West Siberian region of Russia who previously suffered with COVID-19. The study included 260 former COVID-19 patients with varying degrees of severity. The examination took into account the previous history of cardiovascular diseases (CVD) and those with first clinical CVD signs occuring after the infection. VEGF rs699947 and VEGF rs3025039 were genotyped using TagMan probes. The significance of distribution differences in the studied genetic features was determined using a two-way version of the exact Fisher test. We did not find any differences in distribution of the genotype frequencies, both for single polymorphic positions and the complex VEGF-2578/VEGF+936 between the groups with varying degrees of the disease severity (severe, moderate, and mild), both in general group of patients, and in the subgroup of patients with CVD history. Moreover, there were no significant differences revealed between patients with newly emerged CVD after infection compared to patients without similar complications, both for single genotypes and in VEGF-2578/VEGF+936 complexes. According to our data, the functional polymorphism of the VEGF gene at these gene locuses is not associated with either COVID-19 severity, or with cardiovascular disorders accompanying the disease. Changes in VEGF levels may be due to various factors affecting it, thus requiring additional studies.
Type 1 diabetes mellitus (T1DM) is an autoimmune disease characterized by a high risk of vascular complications causing disability and mortality. Immune system dysfunction, especially, imbalance of regulatory T cells (Tregs), plays a central role in pathogenesis of T1DM. Interleukin-2 (IL-2) is a key cytokine for maintaining the Treg function. The T330G (rs2069762) polymorphism in promoter region of IL2 gene may affect its production, but its association with pathological biomarkers of diabetes is not well understood. Our aim was to investigate the possible association between T330G polymorphism of IL2 gene and the levels of laboratory markers reflecting systemic inflammation, endothelial dysfunction, fibrogenesis, and intestinal barrier permeability in T1DM patients. This cross-sectional study included 90 patients with T1DM. Genotyping for the IL-2 T330G polymorphism was performed using PCR method. Plasma concentrations of angiotensin-2, transforming growth factor-b (TGF-b), endothelin-1, C-reactive protein (CRP), markers of intestinal permeability (zonulin, LBP, BPI, sCD14), and other protein factors were determined by ELISA technique. Statistical analysis was performed using non-parametric methods. It was found that the carriers of TT genotype associated with lower IL-2 production, had statistically significantly higher levels of angiotensin-2 compared to the subjects with GG genotype (median 192.4 pg/mL vs. 88.0 pg/mL; p = 0.021). Patients with the TT genotype also showed higher concentrations of TGF-b compared to the heterozygous TG group (median 2.7 ng/mL vs. 1.8 ng/mL; p = 0.015). No significant associations of T330G polymorphism were found with levels of CRP, markers of intestinal permeability, or clinical parameters, including HbA1c and the frequency of The T330G polymorphism of IL2 gene in patients with T1DM is associated with activity of renin-angiotensin system and the levels of TGF-b, the main profibrotic cytokine. The genetically determined decrease in IL-2 production (TT variant of T330G polymorphism) may contribute to hyperactivation of these systems, thus playing a key role in development of vascular complications. This gene variant could be considered a potential genetic marker for risk stratification and personalized therapy in T1DM.
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that predominantly affects small joints, causing persistent pain, functional impairment, and a marked reduction in patients’ quality of life. The pathological process is characterized by ongoing synovial inflammation, destruction of cartilage and subchondral bone, and extra-articular manifestations involving the cardiovascular, pulmonary, and nervous systems. A key pathogenetic factor seems to be an imbalance between pro- and anti-inflammatory mediators, among which tumour necrosis factor-a (TNFa), interleukins IL-17A and IL-17F, and osteoprotegerin (TNFRSF11B), a regulator of osteoclast differentiation, play central roles. The present study aimed to assess the contribution of polymorphisms in the TNFA , IL17A , IL17F , and TNFRSF11B genes to individual susceptibility to RA in the Russian population of the Chelyabinsk Region. We hypothesized that the major genetic impact on disease development may be produced not only by single nucleotide variants but also by their combined multilocus constellations. Special attention was given to intergenic interactions, which are often underestimated in most association studies. Genotyping was performed by polymerase chain reaction (PCR). To evaluate the data, we applied the multifactor dimensionality reduction (MDR) algorithm, which constructs predictive case–control models and evaluates their robustness by means of ten-fold cross-validation and permutation testing. The algorithm identified three most informative combinations comprising four to six SNPs each; every combination showed statistical significance and high predictive accuracy. Cross-validation consistency values exceeded 9/10, indicating excellent reproducibility of the models. These findings confirm that a comprehensive multilocus genotype analysis is more informative than examining individual markers alone and it may be used for patient risk stratification, early diagnosis, and development of personalised preventive strategies based on targeted anti-cytokine therapies. Further studies in larger cohorts are needed to validate these results.
Dental implants are widely used in current dentistry and effectively replace the lost teeth. However, due to concomitant risk factors and low oral immunity, the patients develop peri-implantitis (PI), accompanied by inflammation and general immune response. Meanwhile, the local cytokine profile in saliva remains insufficiently studied. The purpose of this study was to assess cytokine response and evaluate the diagnostic information content of proand anti-inflammatory cytokines in patients with PI. We have examined sixty-five patients with PI aged 50-65 years and 48 PI-free patients aged 50-65 years. The PI diagnosis was carried out based on the results of clinical examination, presence of symptoms, i.e., bleeding during probing, suppuration during probing, bone loss on radiographs ≥ 3 mm, and the depth of the gingival pocket ≥ 6 mm. In saliva samples collected in the morning on rest, the content of several proand anti-inflammatory cytokines was determined by enzyme immunoassay (ELISA) using Protein Contour kits (St. Petersburg). The cytokine profile of patients with PI is characterized by expression of both pro-inflammatory and anti-inflammatory cytokines. The salivary content of IL-1 increased, particularly, among patients with PI (205.9±4.2 pg/mL versus 67.5±3.1 pg/mL in participants without peri-implantitis). IL-6 levels were increased to 29.4±1.3pg/mL versus 11.7±1.2 pg/mL, respectively, showing a significant difference for the both parameters. In addition, the level of IL-19 increased to 54.9±2.3 pg/mL against the comparison group (30.5±1.4 pg/mL); TNFα, to 202.4±3.8 pg/mL compared to 115.6±2.4 pg/mL, respectively (p < 0.001). Moreover, the salivary concentration of IL-4 was significantly increased in patients with PI (18.2±1.4 pg/mL versus 3.8±0.6 pg/mL in comparison group), along with higher IL-10 amounts (66.5±2.7 pg/mL versus 15.3±0.9 pg/mL, respectively, p < 0,001). An estimation by the Kullback information measure revealed the highest diagnostic information content for IL-4 (8.5), IL-10 (8.1), IL-1β (5.7), IL-6 (4.2). To justify the diagnostic criteria, one may recommend usage of IL-4, IL-10, IL-1β and IL-6 levels established in saliva.
Despite a wide availability of specific prophylaxis against viral hepatitis B (HBV), the issues of HBV morbidity among healthcare workers remain quite sufficient. A latent form of hepatitis (LHB) may play a role in maintaining the epidemic spread of HBV. The aim of the study was to identify the dependence of the incidence of anti-HBc antibodies among employees of medical institutions by their age, gender and professional categories. Materials and methods: Blood serum samples were tested for anti-HBc in 1,643 medical staff members (doctors, nurses, paramedics, other personnel). Blood sera were examined for the presence of anti-HBc by ELISA using the HepaBest anti-HBc-IgG enzyme-linked immunosorbent assay system manufactured by Vector-Best-Europe JSC. The results were statistically analyzed using Microsoft Office Excel 2010 and Prism9 (GraphPad, USA). For comparison groups of medical workers according to the frequency of occurrence of Anti-HBc, the chi-square criterion was used. Results. Anti-HBs were detected in 601 persons, thus reaching 36.6% of the total study sample. In 1042 subjects (63.4%), anti-HBs were not revealed. Almost half of paramedical personnel from the study sample were IgG seropositive for the HBV nuclear antigen (50.6%). There were no significant differences in the anti-HBc detection rates for men (31.5%) and women (37.0%). In the structure of seropositive anti-HBc, a smaller percentage was detected in the category “young age” (24.0%), the largest prevalence is noted in the category of “middle age” (45 to 59 years), with 38.8%, which may be associated with service duration and longer exposure to potential HBV sources. The detection frequencies of anti-HBc to HBV nuclear antigen, along with anti-virus surface protein antibodies (anti-HBs) represent an index of HBV prevalence. We would like to recommend anti-HB testing for the medical staff members before repeated immunization and with additional examinations (search for viral DNA with a positive result) in order to exclude medical workers as a source of infection followed by further monitoring of these persons for timely medical aid, as well as adjusting the vaccination volume against HBV in this professional cohort.
Usage of psychoactive substances may cause toxic encephalopathy, which contributes to the modulation of both innate and adaptive immune responses. The impact of psychoactive substances, including those illegal in Russia, upon immune homeostasis remains poorly studied, especially in northern regions with extreme climatic factors. With regard to medical and social consequences, attention is drawn to the rapidly increasing social maladaptation of young patients, as well as the manifestations of organic brain damage. This study is aimed at assessing the ratio of lymphocyte proliferation and apoptosis events in male subjects living in the Northern region of Russia suffering with toxic encephalopathy caused by psychoactive substances. The work included a comparative analysis of immunological parameters of peripheral blood determined in two groups of people living in the Northern region of the Russian Federation, i.e., twenty men with toxic encephalopathy (mean age 33.8±1.8 years) on the first day after severe poisoning with psychoactive substances versus 22 healthy volunteers (34.5±2.0 years, control group). Phenotyping of peripheral blood lymphocytes was performed by the method of indirect immunoperoxidase reaction with monoclonal antibodies. Statistical data processing was performed using SPSS 25.0. The results revealed a statistically significant (p < 0.01) increase in lymphocytes with the CD10 + marker in abusers of psychoactive substances (0.54 (0.40-0.75) × 10 9 cells/L) compared to the control (0.27 (0.16-0.51) × 10 9 cells/L), which indicates hyperproliferation of lymphocytes due to CD10 + . At the same time, a low number of lymphocytes with the CD95 + marker was recorded in men with psychoactive substances abuse compared to the control group, thus reflecting the suppression of apoptosis. A two-fold increase in the CD10 + /CD95 + ratio was established in men with psychoactive substances poisoning, demonstrating an imbalance in proliferative-apoptotic processes. A distinctive feature for men with toxic encephalopathy is an increased content of CD10 + cells that stimulate immune responses via the classical pathway, along with low concentration of lymphocytes with the CD95 + marker, which indicates an increased expenditure of the reserve capacity of immune homeostasis and their reduction. We have also revealed a moderate decrease in the levels of CD71 receptor expression on lymphocytes in males with psychoactive substances abuse. The data obtained indicate that in individuals with toxic encephalopathy in Northern Region, a disruption of both the long-term and short-term mechanisms for maintaining immune homeostasis is observed, being associated with an imbalanced ratio of lymphoproliferation and apoptosis processes.
The ecologically unfavorable Trans-Aral region is characterized by high prevalence of chronic respiratory allergies in children, often combined with anemias. These disorders significantly impact children’s health and require comprehensive study of immune and physiological features. Our objective was to assess the characteristics of cytokine profile in children from different age groups with respiratory allergies accomplished by anemia, depending on the presence of concomitant dermatoses, and level of physical development. The study included 284 children aged 3 to 17 years, divided into three groups: 121 children with respiratory allergies (RA), 126 children with respiratory allergies and concomitant dermatoses (RA + D), and 37 practically healthy children (control group). Concentrations of key cytokines (IL-4, IL-6, IL-10, IL-18, TNFα), and total IgE in blood serum samples were determined by enzyme-linked immunosorbent assay (ELISA). Physical development was assessed using the standardized WHO AnthroPlus methodology. Children with respiratory allergies, regardless of the presence of dermatoses, showed significantly increased levels of IL-4 and IgE compared to controls (p < 0.01), thus suggesting emergence of a dominant Th2 response. The highest level of anti-inflammatory cytokine IL-10 was found in the RA + D group (p < 0.01), likely reflecting a compensatory mechanism aimed at limiting inflammation. Meanwhile, pro-inflammatory cytokines IL-6 and TNFα were significantly decreased in patients compared to healthy children (p = 0.001 and p < 0.001, respectively), thus suggesting probable hyporesponsiveness of the pro-inflammatory pathway in chronic allergic conditions. The levels of IL-4 and IL-10 proved to be lower in children with delayed physical development, while IL-18 was relatively increased, being consistent with literature data and suggesting possible mechanisms of immune dysregulation associated with impaired general health status. The data obtained suggest a predominance of Th2 immune response in children from Trans-Aral Region with respiratory allergies as reflected by increased IL-4, IL-10, and IgE levels. The decreased IL-6 and TNFα levels warrant further study to understand inflammatory processes in chronic allergies under the conditions of ecological stress. Accounting for cytokine profiles and physical development is important for development of personalized therapeutic approaches and improving the disease prognosis.
Some patients with inflammatory bowel disease (IBD) may lack the conventional inflammation criteria, i.e., elevated CRP, ESR and leukocytosis. The aim of this study was to search for additional laboratory risk criteria of IBD in patients with non-specific inflammation markers. The study involved 150 patients divided in two groups: an observation group (100 patients with a verified diagnosis of ulcerative colitis or Crohn’s disease) and a control group (50 clinically healthy individuals). All subjects were tested for complete blood analysis, blood biochemistry. IL-1β, TNFα, and IL-4 concentrations were also assayed. As based on general blood counts and biochemistry testing, the patients from the observation group were divided in two subgroups, i.e., the persons with classic laboratory signs of inflammation, and those without detectable inflammation markers. Three main laboratory blood parameters were assessed for diagnostics of inflammatory process: ESR, white blood cell counts and CRP level. Increase in two or more of the above blood parameters had been considered a positive finding. It was noted that 40% of patients with IBD lacked the non-specific laboratory criteria of inflammation: in 37% of patients with ulcerative colitis, and in 46% of Crohn’s disease cases (p < 0.001). Moreover, we carried out a comparative analysis of cytokine levels and biochemical markers in the blood serum from the controls, and IBD patients without laboratory signs of inflammation. Based on the obtained data, we developed a prognostic model for the IBD probability in patients without non-specific inflammation markers, depending on biochemical and immunological blood parameters. The model included such serum parameters as glucose, sodium and IL-4 concentrations. The predictive ability of the model was assessed using ROC analysis (AUC 0.970±0.018 95% CI: 0.936-1.000; p < 0.001). An algorithm for predicting the IBD risk in patients without non-specific laboratory criteria of inflammation was proposed. The obtained data enable us to identify additional criteria for the IBD risk in patients lacking the non-specific metabolic criteria of inflammation.
The mechanisms of liver regeneration after damage are associated with activation of cytokines. SCF is an important signaling factor since, along with hematopoiesis regulation, it is involved in liver restoration and regeneration after damage. In this respect, the aim of our study was to evaluate SCF levels in blood plasma and liver during physical activity of varying intensity and after Meldonium admonistration. Material and methods: The experiments were conducted with male rats. The study was performed in two stages. Initially, the rats were subject to exertion of varying intensity: the 1 st group of rats performed light physical activity, the 2 nd group underwent moderate exercises, the 3 rd group performed heavy physical activity. A total of 10 sessions of swimming loading were performed. The Intact, sexually mature male rats did not undergo physical activity. The number of these animals corresponded to the number of experimental group. The rat SCF concentration (rat stem cell factor / mast cell growth factor) in blood plasma and the levels of SCF in the liver tissue were determined by means of enzyme immunoassay. The study has shown that SCF level in the intact group was higher in liver tissue than in blood plasma. In the 1 st group of animals, an increase in SCF by 1.5 times in the blood and a decrease in the liver were noted, as compared to the intact group (p < 0.05). In the 2 nd group, SCF contents in the liver was increased, along with a decrease in blood plasma by 1.1 times when compared to the 1 st group. However, this parameter remained higher than in intact animals by 1.4 times (p < 0.05). In the 3 rd group, a decrease in SCF was noted both in blood plasma, and in liver samples as compared to intact animals (p < 0.05). After administration of meldonium during mild and moderate physical exertion, an increase in SCF in the liver by 1.1 times was noted. During severe physical exertion it was 1.4 times higher when compared to experimental animals that did not receive meldonium. Hence, usage of meldonium during physical exercise of varying intensity led to a significant increase in the liver SCF concentration.
The aim of this review is to analyze the role of neutrophils and the mechanisms of “keratinocyte– neutrophil” communication involving IL-17 in the immunopathogenesis of psoriasis based on published scientific data. Psoriasis is a chronic autoimmune disease, characterized by abnormal interactions between epidermal and immune cells. Keratinocytes, when exposed to trigger factors, release alarmins, antimicrobial peptides, autoantigens, cytokines (IL-1b, IL-6, TNFa, G-CSF), chemokines (CXCL1, CXCL2, CXCL8), which promote the activation of skin dendritic cells, IL-23 production, Th17 differentiation, IL-17 secretion, and attract neutrophils to the skin. In the peripheral blood of patients with psoriasis, along with an increase in the absolute neutrophil count, there is an accumulation of activated low-density granulocytes and aged neutrophils with an increased ability to form neutrophil extracellular traps (NETs) and migrate into affected skin; the level of circulating NETs also increases. In the skin, neutrophils realize their proinflammatory potential through degranulation, the formation of IL-1a, IL-1b, IL-6, reactive oxygen species, and NETosis, during which additional externalization of autoantigens occurs. Furthermore, neutrophils “suppliers” of IL-17 to the epidermis. IL-17, via IL-17RA signaling in keratinocytes, enhances the production of neutrophil-activating antimicrobial peptides (S100A7), chemokines (CXCL8), cytokines (IL-1b, IL-6, G-CSF). These cytokines can be transferred from keratinocytes to neutrophils via exosomes and induce the expression of IL-6, IL-8, TNFa, as well as NETosis, which can lead to the release of IL-17. Through NETs, epidermal neutrophils can stimulate TLR4 expression in keratinocytes and the production of IL-36g, CXCL8, CXCL1, lipocalin-2, which enhance the activation and recruitment of new neutrophils into the skin. NETs also induce the synthesis of b-defensin-2 in keratinocytes, which reduces the likelihood of developing infections in affected skin areas. Thus, in psoriasis, the interaction keratinocytes-neutrophils with the participation of IL-17 results in the formation of a “vicious circle” of inflammation. IL-17 also promotes keratinocyte hyperproliferation and impaired differentiation, which, as shown in the zebrafish model, may be due to disruption of cytone-mediated interactions between cells of different epidermal layers. The experimental and clinical data available to date and further study of the “keratinocyte–neutrophil–IL-17” system can form the basis for the selection of new diagnostic and prognostic biomarkers and the development of new therapeutic approaches for psoriasis.
HLA (Human Leukocyte Antigens) genes play a key role in regulating the antitumor immune response and are characterized by significant allelic and population polymorphism. Molecules encoded by HLA genes are involved in the selection of the T cell receptor repertoire, the processing and presentation of neoantigens to T cells, and the regulation of the cytolytic activity of natural killer cells. The structural features of HLA antigens, and especially the characteristics of the antigen-binding site, determine the effectiveness of their interaction with immunocompetent cells, mediating an individual’s susceptibility or resistance to various diseases, including malignancies. Tumor cell evasion of immune control and their unlimited proliferation may result from structural or functional changes in HLA molecules, leading to blockage of neoantigen presentation to cytotoxic T lymphocytes. The causes of such changes may be mutations in the genes encoding the a-chain of HLA class I molecules, the aand b-chains of HLA class II molecules, as well as in the genes encoding the synthesis of proteins necessary for the proper assembly, transport, expression and functions of HLA molecules (for example, b2-microglobulin or the invariant chain of HLA class II molecules). Low or lost expression of HLA molecules on tumor cells also contributes to decreased immune surveillance. Another factor determining the effectiveness of antitumor surveillance is “HLA diversity.” Homozygosity of HLA genes narrows the spectrum of neoantigens that can be presented to cytotoxic T cells, weakening antitumor control. This review analyzes HLA genetic factors associated with the risk of developing a number of hematologic malignancies (acute myeloid leukemia, acute lymphoblastic leukemia, chronic myeloid leukemia, chronic lymphocytic leukemia, and diffuse large B cell lymphoma) in various population groups. HLA markers associated with the response to therapy and long-term prognosis of certain hematologic malignancies are identified. The results of the study of the associations between the HLA phenotype and hematologic malignancies can be used in practice as additional differential diagnostic or prognostic criteria, as well as for the formation of risk groups for developing these diseases.
Diphtheria is a serious infection, often characterized by a pronounced toxic component, which can be accompanied by severe complications of the cardiovascular and nervous systems. The primary method of infection prevention is immunization (primarily in children) with diphtheria toxoid, which induces effective and long-lasting antitoxic immunity. Objective of the study: evaluation of collective immunity to the causative agent of diphtheria among the population of several regions (Amur, Irkutsk, Nizhny Novgorod, Kaliningrad) and the Republic of Crimea. Materials and methods. The cross-sectional cohort randomized study involved 18,207 people uniformly stratified by age (1–5, 6–11, 12–17, 18–29, 30–39, 40–49, 50–59, 60–69, 70+ years), including: 3,576 in Amur; 3,657 in Irkutsk; 3,580 in Nizhny Novgorod; 3,613 in Kaliningrad regions; and 3,781 in the Republic of Crimea. All studies were conducted in strict accordance with the requirements of the Declaration of Helsinki. Immunoglobulin G Abs to the C. diphtheriae toxin were determined in the examined volunteers by enzyme immunoassay using a Russian-made test system. Data analysis and statistical processing were carried out using a web application. Results. The average cohort regional seroprevalence levels were: Amur Region - 82.3% (95% CI: 81.0 - 83.5); Irkutsk - 87.6% (95% CI: 87.6-88.9); Nizhny Novgorod - 86.5% (85.3-87.6); Kaliningrad - 74.2% (95% CI: 72.8 - 75.6); and the Republic of Crimea - 74.8% (95% CI: 73.4-76.1). In some cases, seropositivity did not reach 60%, namely: among individuals aged ≥60 in the Kaliningrad Region and the Republic of Crimea; and among individuals aged ≥70 in the Amur and Nizhny Novgorod Regions. Most volunteers had serum IgG Abs to diphtheria toxin at concentrations of 0.1–1.0 IU/ml, regardless of age, region, or vaccine type. Conclusion. The level of collective immunity mandated by current Russian documents (95% in children, 90% in adults) was practically not achieved in any region or age group (except children aged 1–5 years in the Irkutsk and Nizhny Novgorod Regions). In all regions, the least protected group were individuals aged 60 and older, among whom the seronegative value reached 30–45%.
Neonatalperiodisthetimewhenchildrenareextremelyvulnerableandsusceptibletolethalinfectious complications that could be prevented due to early diagnostic procedures and adequate therapy. Problems with early clinical diagnostics determine the need for searching a marker which could help to differentiate newborn with infection from the newborn with perinatal symptoms resembling infection. Blood microbiological testing frequently gives false negative results, and newborn blood culture tests have low sensitivity. Molecular methods, especially PCR, have also moderate diagnostic accuracy, and can not replace bacteriological blood testing as a reference standard. The same problems exist with C-reactive protein and procalcitonin determination. Ideal marker’s level must quickly rise after contact with pathogen prior to clinical symptoms onset and also quickly decrease after infection healing having high sensitivity and specificity. Cytokines are one of the markers for the infectious process beginning. These molecules are among first to be synthesized after bacterial recognition by pattern-recognition receptors. Their blood plasma concentrations significantly increase during first hours after antiinfectious immune response beginning. That is why cytokines levels determination during neonatal infections may serve as significant tool for early diagnostics and adequate choice for treatment strategy. In this review we tried to summarize existing data on cytokine levels in newborns with neonatal infections and sepsis, and data on its significance in diagnostic approaches. Studies on cytokine levels in newborns are few in number, and reference concentrations are not yet determined. Cytokine family consists of hundreds of molecules, most of them are important mediators of inflammation and sepsis. However not all of them are studied for blood level changes during severe infections in neonatal period. Probably simultaneous studies of several cytokine levels and their synthesis ratio could give new informative data for early neonatal infection diagnostics improvement.
Adoptive CAR-T cell therapy is an innovative approach in oncology that uses genetically modified autologous T cells from the patient as a therapeutic tool to fight cancer. The use of DNA plasmids and in vitro transcribed (IVT) mRNA as vectors for the production of CAR-T lymphocytes has a number of advantages compared to viral vectors, such as the absence of cell genome modification, high transfection efficiency, speed and potentially lower cost of obtaining the final product. In current work, we studied the efficiency of transfection (in terms of cell viability and expression of the target protein) of peripheral blood mononuclear cells and cells of transplanted culture (human embryonic kidney cells, HEK293) by electroporation using model DNA plasmid (pmaxGFP) and IVT-mRNA (mRNA-GFP) encoding green fluorescent protein (green fluorescent protein, GFP). The selection of an optimal transfection regimen was performed. It has been shown that although mRNA-GFP yields a comparable number of cells GFP-expressing cells, the cell viability, and, consequently, general efficiency of transfection is significantly higher when using mRNA-GFP as a vector. At the same time, a comparison of expression level by the cells transfected by two techniques showed that the use of mRNA provides more uniform parameters, whereas usage of plasmid vector results in expression levels differing by several orders of magnitude. The changes in expression level were also tested within 7 days after transfection. It was shown that the proportion of GFP-positive cells decreases with time and does not depend on the method of transfection, while the assessment of the proportion of viable cells showed that plasmid transfection leads to a decreased proportion of viable cells after 7 days to 30%, while the use of mRNA practically does not affect viability (the number of viable cells after 7 days did not significantly differ from the control). The results obtained indicate that the usage of IVT-mRNA may be a more preferable tool in production of CAR-T products by electroporation.
Altered immune response in abdominal sepsis (AS) leads to dysregulation of innate and adaptive immunity, followed by immunosuppression. Mortality rates in AS are quite high, thus requiring continued indepth study of the role of adaptive immunity in this condition. The aim of our study was to evaluate the role of changes in adaptive immunity as a factor of an unfavorable AS outcomes. The control groups consisted of 63 conditionally healthy individuals (33 women and 30 men, group 1). 64 patients with AS aged 32-82 years were also observed. According to their clinical outcomes, we discerned group 2 (n = 46) with a favorable outcome and group 3 (n = 18) with a fatal outcome. The studies were conducted on days 1, 3, and 7. The total number of leukocytes and lymphocytes was determined by the Sysmex XT-1800i/XT-2000i hematology analyzer (Japan). The subpopulation composition of lymphocytes was studied in peripheral blood by flow cytofluorometry using Navios 2/6 flow cytometer (Beckman Coulter, USA) with monoclonal antibody conjugates (Beckman Coulter, USA). The concentrations of IgA, IgM, and IgG were determined by solid-phase enzyme immunoassay (JSC "Vector-Best", Russia). The contents of circulating immune complexes were determined with a microplate reader (Labsystems Multiskan Plus, Finland) using the CIK-HEMA test systems (Hema-Medica, Russia). Statistical processing of the results was performed using the statistical package SPSS 17.0. Analysis of adaptive immunity cells in patients with AS revealed lymphocytopenia: deficiency of CD45+CD3+, CD3+CD4+, CD3+CD8+, immunoregulatory index, CD3-CD19+, marker of early activation of T lymphocytes (CD3+CD25+). A significant relationship was found between the severity of leukocytosis, lymphocytopenia and the outcome of the disease. In cases of favorable outcome, lymphocytopenia was less pronounced than among patients with unfavorable one, along with significantly higher values of the lymphocyte subpopulations: CD45+CD3+, CD3+CD4+, immunoregulatory index, CD3-CD19+, CD3+CD25+, CD3+56+. Meanwhile, the number of CD3+CD8+, CD3+HLA-DR+ lymphocytes in the surviving patients was decreased over 7 days, as compared with the unfavorable outcome group. More pronounced leukocytosis was associated with unfavorable outcome of AS, thus emphasizing severity of the systemic inflammatory response, which is closely associated with severity of clinical course and prognosis of AS. There was a more pronounced lymphocytopenia, a progressive decrease in the following lymphocyte subpopulations compared to the survivors: CD45+CD3+, CD3+CD4+, immunoregulatory index, CD3-CD19+, CD3+CD25+, CD3+56+. The values of CD3+CD8+, CD3+HLA-DR+ lymphocytes in fatal cases were higher than in favorable cases. The results of our study emphasize the need to take into account the state of adaptive immunity in order to more accurately stratify the risk of death and personalize therapeutic strategies.
Excessive alcohol consumption has a negative effect on hematopoiesis, which manifests with significant suppression of both blood cell production, and structural changes in hematopoietic precursors, i.e., by suppression of their maturation, up to pancytopenia. One may distinguish between the direct effect of alcohol (toxicity to bone marrow, hematopoietic precursors and mature blood cells), and the indirect action caused by deficiency of trophic factors. Alcohol addicts often develop anemia, due to premature destruction of erythroid cells. Thrombocytopenia, also being an important feature of hematological disorders in alcoholism, results in spontaneous bleeding and petechiae. Chronic alcohol consumption also has a suppressive effect on production and functioning of white blood cells, resulting in poor resistance to bacterial infections. We have previously identified the immunomodulatory properties of an innovative anticonvulsant, meta-chlorobenzhydrylurea (m-CBHU). Its positive effect was determined upon intragastric administration in long-term alcoholized mice, In a recent study, splenic lymphocytes, being in vitro exposed to the mentioned anticonvulsant, have shown a positive psychoneuromodulatory effect during chronic ethanol intoxication. These effects seem to proceed via relatively independent mechanisms. In this study, the effects of intravenous transfusion of m-CBHU-treated spleen lymphocytes on bone marrow hematopoiesis and peripheral blood cells were tested in murine model of chronic alcoholism. In the bone marrow of syngeneic recipients (long-term alcoholized mice), a decreased colony-forming activity of hematopoietic precursors was observed: the population of erythroid precursors was significantly reduced. Decreased counts of granulocyte-macrophage precursors were also detected at a trend level. The only exception was the population of early progenitors, where the number of colonies did not change. In peripheral blood, a decreased number of lymphocytes, platelets, erythrocytes and leukocytes was observed associated with increase in the population of segmented neutrophils, suggesting peripheral inflammation. Lymphocytes pre-cultured with meta-chlorobenzhydryl urea, after intravenous administration to syngeneic long-term alcoholized recipients, had a corrective effect on a number of hematopoietic parameters, which manifested with restoration of the colony-forming activity of bone marrow hematopoietic precursors to the levels comparable to those in intact age-matched mice, along with decrease of segmented neutrophils and restoration of RBC and lymphocyte counts as wells as a tendency for increase in platelet counts in peripheral blood. The data obtained may suggest the efficiency of meta-chlorobenzhydrylurea-modulated lymphocytes in correction of distinct changes in hematopoiesis associated with long-term ethanol intoxication.
Synthetic peptides provide a promising basis for HIV vaccine development. Following their administration, the immune response is focused only on a specific epitope. Moreover, they are able to activate both humoral and cellular pathways of immune response, being safe and well tolerated. Due to low molecular weight, the synthetic peptides exhibit low immunogenicity, therefore requiring usage of various immunoadjuvants in immunogenic compositions. The V3 loops of gp120 envelope protein are among the main protective epitopes, with a number of monoclonal antibodies with broad neutralizing activity having been obtained to this antigen. We have studied the immunogenicity of peptides copying the V3 loop of the group M HIV-1 virus consensus sequence, and the Russian viral isolate RUA022a2. We have also assessed the possible impact of its administration route (subcutaneously versus intraperitoneally) and usage of an immunoadjuvant. poly(I:C), a synthetic analogue of double-stranded RNA, being a ligand of TLR3 innate immunity receptors, was used as an adjuvant. The studies were conducted on Balb/c mice. It has been shown that the route of administration did not affect an immune response development to the tested peptides. However, earlier production of specific IgG antibodies was observed in the groups treated with immunoadjuvant. At the same time, the antibody titer was slightly higher in the groups where peptides were administered with the adjuvant after the 3 rd (last) administration. No differences have been revealed in the isotypes of induced antibodies. IgG1 antibodies were predominantly induced in all groups. Specific IgM antibodies were detected only after 3 rd injection of the antigens. The antibody titer did not depend on the administration route, being slightly higher in the groups where peptides were administered with the poly(I:C) adjuvant. The induced antibodies did not exhibit neutralizing activity against the QF495.23.M.EnvA1 isolate. When studying antigen-specific cellular immune activation, the production of IFNγ, the Th1 response marker was detected only in poly(I:С)-treated groups. In addition, a low level of anti-inflammatory cytokine IL-10 was determined in groups where poly(I:С) was included in the immunogenic composition. Moreover, the highest IL-10 level was detected in groups with intraperitoneal administration. Our studies have shown that the use of poly(I:С) adjuvant promotes immune response to the synthetic peptides, thus contributing to earlier induction of specific antibodies as well as switching to the Th1 pathway. The data obtained may be used for development of vaccines against HIV and other viral infections, in order to increase their immunogenicity and ability of inducing a protective immune response.
Global studies show that valvular heart disease still takes one of the leading places in the structure of mortality from cardiovascular diseases, being among the major causes of heart failure, including those among the employed population. Xenogeneic tissues are widely used in cardiac surgery, both in biological prosthetic heart valves, and as vascular and intracardiac patches. Modern chemical methods of xenogenic tissue treatment aimed at elimination of its immunogenicity but they do not, however, completely remove xenoantigens from the tissues. The residual carbohydrate antigens are thought to be a trigger of immune response against the animal xenotissues. At the same time, the role of immune response to xenogeneic antigens for induction of inflammation, valve dysfunction, and calcification are under discussion. The aim of this review was to summarize the research data on immune response to xenogeneic tissue implanted into the heart, and to find tools of preventing this immune conflict. Modification of pericardium of large animals by various methods does not entirely remove carbohydrate epitopes from extracellular matrix and cell membranes, which are recognized by pre-existing antibodies of M and G classes. The highly dynamic functioning of xenogeneic biological prostheses increases their antigenicity by reducing the primary cross-linking of extracellular matrix and activating the alternative complement pathway associated with adsorption iC3b complement component on xenogeneic tissue, serving as an opsonin for micro- and macrophages. The inflammatory endotypes of individual patients may be genetically determined by increased synthesis of certain cytokines. In particular, rheumatic heart disease, as a basis for the disorders of mitral heart valves, is characterized by an increase in TNFα, IFNγ and IL-6. Any of these cytokines may be targets for biological therapies aimed at limiting the constitutional inflammatory endotype. The OMICs technologies applied to various studies of biological degradation of xenogeneic heart valve prostheses, their implantation, and wide clinical examination of patients, may help us to find novel variants of immune-inflammatory endotypes leading to dysfunction of bioprostheses, and to identify target molecules for potential inhibition of antixenogeneic immune response.