The review article analyzes literature data on the issues of immune response dysregulation during aging. It has been shown that impairment of innate and adaptive immune response in elderly and senile people under the conditions of spreading the new coronavirus infection is an aggravating factor in the course of the disease and recovery. Neuro-immuno-endocrine changes occurring in the organs of immune system, immunocompetent cells, molecules and receptor formations involved into the arising immune response have been traced. The imbalance of the brain-intestine-microbiota axis is considered in sufficient details, where a significant role is attributed to the changes occurring in hypothalamic-adrenal system under participation of biogenic neurotransmitters and neuromodulators. It is shown that intestinal microbiota may be involved into the neurodegeneration events, due to toxic effects on the brain via the neuro-immuno-endocrine and metabolic pathways. The data are presented, which show that adrenaline, norepinephrine, dopamine and serotonin are involved in the immune response dysregulation, thus making this process similar to the changes that occur during the general adaptation syndrome and stress response of the body. On the other hand, the review notes that chronic stress during aging not only alters the activity of macrophages, lymphocytes and dendritic cells, but also increases the level of proinflammatory cytokines in blood, thereby affecting permeability of the blood-brain barrier. The article emphasizes that with body aging, a neuroendocrine sensory pathway of immune response dysregulation is gradually formed. In this regard, it is noted that the afferent nerve endings and neurons of the vagus, adrenergic and peptidergic nerves are involved into dysfunction of immune system by affecting the processes occurring not only in thymus, but also in the brain. However, it is obvious that the pathodynamic “dysadapting circuit” formed in the higher compartments of nervous system is also involved in dysregulatory immune responses during aging. Hence, the work concludes that the signaling networks of the body's regulatory systems (nervous, immune and endocrine) are closely interconnected throughout the lifetime, but with aging and penetration of antigens into the body, this interaction is easily disrupted at different levels of organization of living matter, thus leading to dysregulation.

This review describes principles of action and the method of delivery of mRNA molecules into cells, as well as some of developed RNA vaccines and the results obtained in their study, though they have not been authorized for use yet. In addition, the review discusses efficacy and safety proved for RNA vaccines registered for COVID-19 prevention at the time of writing. The development, clinical trials and market launch of RNA vaccines for mass immunization in a few months can be considered one of the major breakthroughs in pharmacology over the past year. Despite of all seemingly indisputable advantages, none of RNA vaccines had reached Phase III of clinical trials since the moment of its discovery in 1993 until last year. The first experience of the successful use of mRNA vaccines was back in the 90s of the last century, when vaccination of mice with liposomes encoding an antigen-encoding mRNA was found to initiate specific immune response in mice. However, in these years, the method did not find application, due to the toxicity of lipids used. Subsequently, a large number of attempts have been made to develop vaccines against other viral infections, including Zika virus, Dengue virus, Ebola virus, cytomegalovirus, influenza virus and others. Despite the importance for preventing the spread of these diseases, the development of a vaccine preparation is a rather lengthy process, and final success is not guaranteed. However, the COVID-19 pandemic has become speeded the development of mRNA vaccines up.

At the time of writing the review, two mRNA-based vaccines have been registered only in the world, both, BNT162b2 and mRNA-1273, were against COVID-19. Their effectiveness and safety are still actively studied. Moreover, it took less than a year for new strains of SARS-CoV-2 to appear, and the efficiency of vaccines against them was found to be lower than against the reference pathogen variant. Considering that the three new strains of SARS-CoV-2, “British”, “African” and “Brazilian”, are rapidly spreading in the world, the first results of efficiency evaluation of vaccines against them have already been published. One may expect that, considering mutations in these strains, the BNT162b2 and mRNA-1273 vaccines will remain effective against the “British” strain, but their protective properties are greatly weakened against the “African” variant.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) belongs to the group of growth cytokines (hematopoietins) that regulate proliferation and differentiation of myeloid lineage cells. Recently, a lot of new data have accumulated, indicating the presence of a number of previously unknown biological effects in GM-CSF and synthetic peptides of its active center, which open up new prospects for their wide clinical use.

The review outlines current understanding of the structure, functions, and mechanisms of GM-CSF action and concerns the structure of its receptor. The GM-CSF producer cells are characterized, as well as target cells (effector cells) responding to this cytokine are also presented. The known mechanisms of intracellular signaling involved into the GM-CSF/receptor interaction are described. The main pleiotropic effects of this cytokine as a factor of hematopoiesis and an immunostimulating agent are characterized. The previously known and recently found immunobiological effects of this cytokine, its recombinant forms and synthetic analogues of its active center are discussed.

Participation of GM-CSF in hematopoiesis and differentiation of myeloid cells, the effects of this cytokine on the functional activity of immunocompetent populations (lymphocytes, macrophages, neutrophils, dendritic cells) and tissue cells were characterized. The influence of GM-CSF on the development and course of infectious and inflammatory processes, its role in the creation of combined vaccines is reviewed. Clinical data on usage of GM-CSF and its recombinant forms in hematology, immunology, oncology, reproductive medicine and in the treatment of systemic autoimmune processes and infectious diseases are presented.

The recently discovered immunobiological properties of synthetic peptides derived from active center of GM-CSF are summarized, indicating that they exhibit immunotropic and hematopoietic effects, as well as antimicrobial activity against Gram-negative and Gram-positive bacteria, viruses, and tissue repair (effect on the rate of wound healing), which is not typical to the whole GM-CSF molecule. We discuss the prospects for clinical applications of synthetic GM-CSF analogue (ZP2 peptide), and an opportunity of creating new cosmetics and pharmaceuticals with combined immunostimulating, antimicrobial and reparative properties on its basis.

The review expands the view on potential usage of cytokine therapy in the treatment of various infectious and non-infectious diseases in humans, and is addressing a wide range of specialists working in the field of allergology and immunology, infectology and regenerative medicine.

Impairment of immunological reactivity in inflammatory periodontal diseases is well proven. To perform immunomodulatory treatment in domestic dental practice, various medications are used, including natural, chemically modified, recombinant, genetically engineered and synthetic substances, which differ in their effects upon innate and adaptive immune systems. Complex preparations of natural cytokines as well as genetically engineered preparations of IL-1, IL-2, growth factors, IFNα, IFNβ, IFNγ are applied in clinical settings. Clinical implementation of interferon and interferon inducers in combined therapy of generalized periodontitis is shown to increase resistance to viral components of the oral microbiota. Growth factors (platelet growth factor, fibroblast growth factor, endothelial growth factor, etc.) are successfully used for tissue regeneration in periodontics and maxillofacial surgery. Experimental studies have shown that local administration of toll-like receptor-9 and CD40 ligand may reduce periodontal ligature inflammation and bone loss in mice by inducing B-cell proliferation and increasing IL-10 mRNA expression. Promising results in development of new biologically active drugs are obtained with nanotechnology approaches, i.e., production of composite materials of metal nanoparticles with polymers, growth factors, and local application of these products. General limitations of all these growth factors include extremely short periods of biological activity, and adjusted duration of local effective concentrations. Therefore, it is important to develop a drug delivery system using appropriate scaffolding elements thus allowing local effects of the drug for a certain period of time. In experimental models, alginate hydrogels performed well upon local delivery of granulocyte-macrophage colony-stimulating factor and stromal lymphopoietin of the thymus. A new immunomodulatory strategy for alveolar bone regeneration targets macrophages. A biologically functionalized injectable microsphere of heparin-modified gelatin nanofibers that mimic the architecture of the natural bone extracellular matrix, and provide an osteoconductive microenvironment for bone cells includes IL-4, which has heparin-binding domains. These medications represent a component of a comprehensive treatment schedule, and should be evaluated for immune status before and after therapy. Thus, recent advances in studies of innate and acquired immune responses in inflammatory diseases and, in particular, in periodontal disorders, allows us to develop new approaches and methods of treatment in order to improve efficiency of complex therapy in the inflammatory periodontal diseases.

Systemic inflammation is known to be a key component of infection and non-infection diseases progression and may lead to multiorgan failure, persistent inflammation, immunosuppression, catabolism syndrome or even indolent death. This importance dictates the need for relevant in vivo models of inflammation to investigate the pathogenesis of numerous diseases and to perform drug screening. Danio rerio (zebrafish) became one of the most important models to explore biological processes in vivo. The aim of the study was to generate a lipopolysaccharide (LPS) model of systemic inflammation in vivo using zebrafish and to identify organspecific proinflammatory genes activity after intraperitoneal LPS infusion. We performed organ specific analysis of main proinflammatory genes expression in zebrafish after LPS stimulation. Comparing 18s, eef1a1l1, gapdh, and actb as potential housekeeping genes, we came to conclusion that eef1a1l1 with 99% effectiveness is the most promising for further normalization in this model. The genes activity was the most pronounced in the heart where the expression of IL6, CXCL8a, and CXCL18β was increased up to 100-fold. Moreover, the kidneys were the most involved in the inflammatory process since the highest number of analysed genes were up-regulated there: expression levels of CXCL18β, CXCL8a, IL1β, IL6, Mpeg1.2, and TNFa were significantly increased. This was probably related to the kidney activity as an immune and hematopoietic organ. The lowest reactivity was detected in the muscles. Immune reactions could be dose-dependent, for instance the infusion of 20 µg LPS led to decrease of expression of IFNy, Mpeg 1.2, and Mpeg 1.1 in the liver and to increase of Mpeg 1.2 expression in the kidney comparing with 10 µg dosage. Thus, due to the high degree of the similarity and other unique properties, Danio rerio has the advantage of being relevant model of inflammation. Our model demonstrated that the investigation of isolated zebrafish organs could be useful and informative for the investigation of inflammatory processes.

Behcet's disease (BD) is a systemic disease underlyed by chronic vasculitis. Hyperactivity of innate and adaptive immunity plays important role in its pathogenesis. Uveitis occurs in 30-70% of the patients, often recurring and reducing visual function. The objective of our work was to study the features of systemic production of immune mediators in BD patients, depending on presence and activity of uveitis. 116 BD patients were divided into 3 groups: (1) 41 patients with active uveitis (UA), (2) 64 subjects with uveitis remission (UR), (3) 11 uveitis-free BD patients (WU). Control group (CG) comprised 34 conditionally healthy people. Detection rate (%) and contents (pg/ml) were measured for IL-1β IL-2, IL-4, IL-5, IL-6, IL-12p70, IL-13, IL-18, IFNγ, CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β, CCL5/RANTES, CCL11/Eotaxin, СXCL1/GRO-α, CXCL8/IL-8, CXCL10/IP-10, CXCL12/SDF-1α, GM-CSF, TNFα in blood serum by means of multiplex analysis using MAGPIX analyzer (Luminex Corp., USA), Procarta Plex “Human Th1/Th2&Chemokine Panel 20 plex” kits (Bioscience, Austria). TGF-P1, TGF-P2 levels were assayed by ELISA-test (“Vfector-Best”). All the BD patients showed high detection rates of CXCL1/GRO-α (but not its level) in comparison with CG. Detection rate and levels of IL-6, IL-8 were increased in 1^st and 2^nd BD groups, compared to CG. In UR, unlike UA and WU groups, IL-4 was detected more often than in CG. WU patients showed increased detection rate of only CXCL1/GRO -α. When compared with UA, WU patients had lower serum concentrations of IFNγ, MCP-1, IP-10, MIP-1a, SDF-1α, TGF-β1; UR patients also showed decreased serum levels of IL-18, Eotaxin, GRO-α, RANTES, TGF-β2. Our results indicate the importance of angiogenic and proinflammatory chemokines and cytokines in pathogenesis of BD uveitis, as well as imbalanced production of various immunomediators. Higher detection rates and levels of IL-6 and IL-8 in UA and UR patients may result from weak persistent intraocular inflammation, even upon relief of clinical symptoms, thus, probably, requiring therapeutic correction.

Overweight and obesity are among the main factors of cardiovascular risk, but the prospective studies on the dependence between high-fat diets and weight gain yielded contradictory results. Different types of fats exert varying metabolic effects, and this fact leads to a difference in the risk associated with increasing body weight. The effects of fat quality in the daily diet on immunological status and resistance of myocardium to ischemic-reperfusion damage should be studied experimentally in biomedical models. The purpose of this work was to assess the effect of the qualitative composition of a high-fat diet used for induction of primary visceral obesity (PVO) in rats with systemic inflammatory response syndrome (SIRS) upon myocardial resistance to ischemic-reperfusion injury, and levels of pro- and anti-inflammatory cytokines.

The experiments were performed on adult male Wistar rats with PVO caused by 28-day consumption of any fat types: hydrogenated fats (HF), vegetable oils (VO), animal fats (AF) or milk fat (MF). The SIRS model included a combination of chemically induced colitis (CIC) and intragastric injection of a broad-spectrum antimicrobial agent (AMA) for three days. Five days later, immunological and biochemical studies were conducted, as well as composition of intestinal microbiota in faecal samples, morphological changes in the structure of the large intestine, hemodynamic parameters and myocardial resistance to ischemic-reperfusion injury were studied in the model of isolated heart perfusion, by Langendorff technique.

There was a significant increase in the concentration of anti-inflammatory cytokines in animals with SIRS, i.e., TNFα, IL-1α, IL-2, IL-8, as well as a decrease in TGF-1β, an anti-inflammatory cytokine. SIRS was accompanied by severe dietary disorders and evacuatory function of the gastrointestinal tract. Minimal changes in the intestinal microbiota composition, as well as the most pronounced regeneration signs of intestinal epithelium was observed in rats in the group with MF injection. There was a trend for increasing size of infarction in all the groups as compared with control, directly correlating with increase in BDNF and IL-2 production. However, a significant increase in the infarction size was found only in the group receiving milkfat, thus suggesting a decrease in myocardial resistance to ischemic reperfusion injury (IRI).

Thus, the presence of SIRS in the primary obesity model is characterized by controllable change of inflammation markers and depends on the quality of dietary fats. The degree of morphofunctional deterioration of isolated heart, including a decrease in resistance to ischemia-reperfusion injury, correlates with the concentration of BDNF and IL-2 during the studied observation terms.

The action of checkpoint inhibitors is based on activation of T cell antitumor immunity, and, therefore, the search for markers of lymphocyte functional activity before starting the therapy is highly relevant. Determination of the PD-L1 expression in tumor tissues reflects immunosuppressive activity of malignant cells, and it is used as a predictive marker in clinical practice. The ratio of neutrophils to lymphocytes in tumor tissue and in peripheral blood can also indicate the activity of adaptive immunity and correlates with the efficacy of therapy. It has been shown that a high level of interleukin 1 beta in the tumor microenvironment is associated with immunosuppression of lymphocytes and, possibly, reflects the activity of the tumor microenvironment. The aim of this work is to study the relationship between tumor expression of PD-L1, the concentration of serum interleukin-1 beta and the ratio of neutrophils and lymphocytes in peripheral blood.

Before starting therapy with checkpoint inhibitors in patients with various solid tumors (n = 50), the serum level of interleukin-1 beta was determined by ELISA (ELISA-Best, Novosibirsk, Russia), expression of PD-L1 in the tumor by immunohistochemical method, complete blood count was performed using cytometry. Statistical analysis was performed in GraphPad Prism 6 (Graph Pad Software, USA) using the statistical methods of Fisher, Mann-Whitney, and Spearman.

The average value of the index of the ratio of neutrophils and lymphocytes (NLR) in peripheral blood was 2.65± 0.21 (95% CI 2.22-3.07). The index value of more than 3.5 was found in 18% (9/50) of patients. The mean value of the PD-L1 expression level was 23.02±4.52% (95% CI 13.86-32.18). Expression of PD-L1 in tumor tissue was detected in 60.1% (25/40) of patients, among whom an increased expression of more than 50% was detected in 20.0% (5/25) of cases. A positive weak correlation was found between the concentration of interleukin 1 beta and the number of leukocytes (r = 0.34; p = 0.019) and index (r = 0.32; p = 0.029). The level of PD-L1 expression in tumor tissue also had a weak positive correlation with the serum interleukin 1 beta concentration (r = 0.33; p = 0.037) and the neutrophil-lymphocyte ratio (r = 0.33; p = 0.034). In the group of patients with PD-L1 expression > 5%, the mean value of the concentration of interleukin 1 beta was 1.65±0.62 pg/ml, and the mean value of the index was 4.26±0.94 х 10 9/l, which exceeds the values groups with undetectable PD-L1, but the differences were not statistically significant.

The obtained result may indicate the influence of the immunosuppressive properties of the tumor on the state of the patient's immunity. Comprehensive determination of tumor PD-L1 expression, serum interleukin 1 beta concentration and the ratio of neutrophils and lymphocytes in peripheral blood can be used as an assessment of the patient's immune status before starting treatment with checkpoint inhibitors.

Male infertility is a multifactorial disease, and elucidation of etiopathogenetic mechanisms of its progression is a topical issue. High percentage of the “idiopathic infertility” diagnosis is largely cased by inability to establish etiology of decrease in reproductive spermatic function. Mutation of в-defensin DEFB126 gene is supposed to affect the fertilizing ability of spermatozoa at different levels: it may decrease their ability to migrate through the cervical mucus and reduce binding capacity to epithelial layer of upper female reproductive tract, and it may also increase susceptibility for infections of reproductive tract, due to impairment of local protective function of defensins. Thus, the aim of the present study was to examine possible role of rs11468374 gene polymorphism of the DEFB126 gene in pathogenesis of male idiopathic infertility. Patients and methods: The group of patient with decreased fertility included 54 male subjects, ages 34 to 42, with a control group of 19 ejaculate donors without acute or chronic disease aged 28 to 36. The indicators of sperm motility in the Moscow population were compared with individual levels of DEFB126 gene expression, as well as with estimated distribution frequency of rs11468374 alleles and genotypes among the subjects.

As compared with the control group, the infertile patients exhibited a more than seven-fold reduction of DEFB126 gene expression. Analysis of distribution frequency for alleles and genotypes rs11468374 polymorphic marker of the DEFB126 gene revealed that the mutant allele is detected almost twice as often in males with infertility, as compared with control group. No cases with the DEFB126 del/del genotype were found among the control group, in contrary to 16.1% in the group of patients. The patients with DEFB126 del/del genotype exhibited 5.2-fold reduction of sperm motility. Thus, the data obtained may be used to extend our knowledge on the pathogenetic mechanisms of male idiopathic infertility and to improve techniques for its diagnostics, as well as to provide personalized approach to the treatment of male reproductive disorders. The association between carriage of del mutant allele and decreased level of sperm motility suggests a role of this polymorphism in pathogenesis of male infertility. A general decrease in the level of DEFB126 gene expression in the patients affected by infertility also presumes a contribution of defensin 126 to pathogenesis of the disorder.

The graft-versus-host disease (GVHD) is among the most common complications after hematopoietic stem cell transplantation (allo-HSCT). The main tools for GVHD prevention remain calcineurin inhibitors (cyclosporin A, tacrolimus), methotrexate, mycophenolate mofetil. Upon implementation of reduced-intensity conditioning regimens, antithymocyte globulin was widely introduced. However, negative effects upon reconstitution of T-cell immunity have been noted, thus increasing risk of severe infectious complications and disease relapse. With extended practice of HSCT from alternative (partially matched or haploidentical) donors, cyclophosphamide was increasingly used. Our aim was to study reconstitution of immune cell subpopulations in the patients undergoing bone marrow transplantation (BMT), when using different GVHD prophylaxis regimens, including the schedules with post-transplant CP usage. The study concerned 44 cases classified into 2 groups. The first one included patients with standard immunosuppressive therapy, antithymocyte therapy, cyclosporine A, methotrexate, mycophenolate mofetil. The second group included the patients who received CP as immunosuppressive drug combined with other treatments (cyclosporine A, methotrexate, mycophenolate mofetil). At specified control terms, (D+14, +30, +60, +90) the blood leukocyte subpopulations were assayed by means of multicolor flow cytometry. Absolute counts of CD4+ cells in HSCT recipients treated with CP post-BMT proved to be sufficiently lower at D+14 and +30, than in those treated with classical immunosuppressive therapy. However, at later terms, (D+60, +90), these differences were not observed. Moreover, in CP-treated bone marrow recipients, absolute numbers of CD8⁺ cells was significantly higher, compared to the patients who received conventional GVHD prophylaxis. Reconstitution of the studied lymphocyte populations in hematopoietic cell recipients did not depend on the GVHD prophylaxis regimen. Usage of CP combined with bone marrow as a source of stem cells, brings about sufficient decrease of some cell populations (CD4⁺; CD8⁺; NK cells) at early terms post-transplant. Administration of CP combined with hematopoietic stem cells as the source of hematopoietic graft seems to be more reasonable.

The aim of the present study was to assess safety and clinical efficacy of inhalation immunotherapy based on intranasal administration of bioactive factors produced by the M2 phenotype macrophages in children with language impairments, as well as to study the effect of inhalation immunotherapy on the cytokine profile in the patients' blood serum. The study was carried out according to the NCT04689282 protocol (www.ClinicalTrials.gov) and included 14 children (9 boys / 5 girls), aged 3 to 8 years, with language impairments associated with perinatal or postnatal CNS lesions of various origin. The children recruited into the study were assessed by a neurologist and speech therapist before the therapy, at the end of the course (1 month), and 6 months later. Serum samples for cytokine analysis were obtained before and 1 month after therapy. The course of intranasal inhalations by the conditioned M2 media (2 ml one time per day for 28-30 days) was safe and well tolerated. None of the 14 treated children had significant adverse reactions and severe undesirable events. Intranasal immunotherapy led to a decrease in the severity of language problems, which manifested by improved speech understanding by 45%; the sensorimotor level of speech, by 51%; word formation skills, by 72%, as well as a twofold increase in general and fine motor skills. In children with signs of autism spectrum disorders, along with a language improvement, a decrease in the severity of autistic symptoms was registered, as evidenced by statistically significant decrease in the CARS score from 42.5 to 38.5 after 1 month, and to 33 points after 6 months (p < 0.05). The clinical effect was revealed rather soon, i.e., within a month after the first procedure, being maintained or intensified during a follow-up for 6 months. At the same time, two-thirds of the children showed a clear clinical improvement, with insignificant effect in the rest of patients. Comparative analysis of the serum cytokine levels in these subgroups showed that children with a pronounced positive response to inhaled immunotherapy differed in the following parameters: (1) initially higher level of VEGF and IGF-1, and (2) decrease the level of TNFα in response to intranasal immunotherapy. In summary, we first tested a fundamentally new approach based on the use of soluble factors from M2-type macrophages and intranasal route of their administration in order to treat the children with severe language impairments, demonstrating safety and obtained preliminary data on effectiveness of such approach.

The task in treating acute nasopharyngitis (ANP) deals with reducing the disease symptoms and the risk of complications. The lack of reliable antiviral drugs makes it important to search for appropriate medicines among other pharmacotherapeutic groups.

The study involves a comparative analysis of the efficiency and estimates potential: the recombinant interferon α2b and the compound containing fungal β-D-glucans used in treat ANP

The studies involved patients with ANP from 18 to 55 years old. As many as 152 people were examined including the following: 38 were practically healthy people (group 1); and 114 patients wuth ANP: 38 people (group 2) was subject to a standard therapy (vasoconstrictor nasal drops, nasal cavity irrigation using 0.1% Miramistine solution, gargling using the Furacilin solution); forty people (group 3) were administered application of intranasal interferon α2b of 10⁵ IU, it was delivered with a spray into each nasal passage twice a day; 36 people (group 4) were administered an immunotropic drug containing β-D-glucans orally twice a day. The duration of drug administration lasted 7 days. Polymerase chain reaction (PCR) was used to identify the ANP etiological factor. Concentrations of cytokines IL-1β, IL-1ra were estimated using enzyme immunoassay (ELISA) technique. Clinical efficiency was assessed through score approach. The following symptoms were taken into account: general malaise, sore throat, character of nasal discharge, and the difficulty of nasal breathing. The results of the study were analyzed using parametric and nonparametric statistical methods. In 60.0% the nasal secretions of patients revealed RV. The distribution of cytokine concentrations in nasal secretions in group 1 indicated that the concentration of IL-1β was in the range of 20.0-25.0 pg/ml, and the concentration of IL-1ra was about 1250.0-2500.0 pg/ml. Developing ANP stimulated an increase in IL-1β concentration up to 30.0-70.0 pg/ml in nasal secretions of patients without affecting IL-1ra concentrations. On day 7 of treatment, the cytokine concentrations among the patients treated using the immunotropic drugs were the same as in the group of healthy individuals. There were no significant changes in cytokine production on day 7 in the group of patients undergoing the standard treatment. Application of proposed immunobiological medicines to ANP does not result in overproduction of proinflammatory cytokine IL-1β in nasal secretion. This confirms that these drugs are promising in the treating strategy including reduction of the risk of developing complications.

Detection of subcellular structures containing typical citrullinated rheumatoid autoantigens in a single compartment presents a special interest, due to importance of anticitrulline autoantibodies for the autoimmune response in RA. Neutrophil and monocyte extracellular traps (NETs and ETs, respectively) may be considered such candidate structures. Our objective was to assess ability of blood neutrophils and monocytes from RA patients to generate NETs and ETs spontaneously and after in vitro induction.

32 patients with verified RA and 30 healthy volunteers as controls were included into the study. Circulating neutrophils and monocytes were isolated with one-step density gradient centrifugation using three layers of ficoll-amidotrizoate gradient. Composition of isolated cellular fractions, their viability, and non-specific activation were evaluated microscopically using Trypan Blue exclusion test, as well as Nitro-Blue Tetrazolium test. The NETs were induced by phorbol-12-myristate-13-acetate, and ETs by bacterial LPS. Spontaneous and induced formation of extracellular traps was assessed using fluorescence microscopy. Neutrophil and monocyte fractions contained minute percentages of impurities and low extents of activated and dead cells. Spontaneous NET and ET formation in RA patients was significantly increased comparing to healthy controls. Neutrophils from ACPA-positive RA patients were found to have higher frequency of NET formation, compared to ACPA-negative RA patients. The monocytes did not demonstrate such differences between these subgroups. There were no substantial morphological differences in NETs and ETs patterns between the individuals from both groups. Induced extracellular trap production in RA was significantly higher compared to healthy controls. The level of myeloperoxidase-specific fluorescence in ETs was considerably lower than in NETs. NETs could probably be considered as a source of citrulline autoantigen participating in autoantibody production and stimulation of inflammatory autoimmune responses in RA, whereas ETs may play less important role in this process.

At present, a search for promising ways to diagnose infection caused by SARS-CoV-2 is quite relevant. Oral fluid is not commonly used for assessment of COVID-19 risk. Its molecular profile reflects both local state of the oral cavity, and individual organs and systems, thus suggesting a reliable diagnostic platform. Systemic inflammatory response is known to play a crucial role in development of the coronavirus infection; the “cytokine storm” determines severity of the disease. The saliva-based diagnostics of clinical course in COVID-19 patients includes determination of IL-6, IL-8, C-reactive protein in oral fluid, in order to assess severity of the inflammatory process. The present study was carried out at the Department of Fundamental and Clinical Biochemistry with Laboratory Diagnostics, and Department of Pediatric Infections at the Samara State Medical University. The study involved 122 persons: 67 clinically healthy individuals comprised the control group, and the group of comparison included 55 inpatients with moderate or severe coronavirus infection (COVID-19) caused by SARS-CoV-2 virus as confirmed by PCR and/or ELISA testing. Development of the disease was accompanied by drastically increased contents of IL-6 and IL-8 in oral fluid of the patients relative to the indexes in healthy persons, i.e., several-fold for IL-6 (+ 650%) and even higher elevation of IL-8 levels (+ 26513%), as well as a 2-fold increase of C-reactive protein (+115%). When comparing the immune indexes of oral fluid in presence versus absence of respiratory insufficiency, a significant difference was found for salivary IL-6 (+173%) in the patients with grade 1-2 respiratory insufficiency as compared with patients free of respiratory disorders. Determination of these proinflammatory markers in patients with COVID-19 is of important prognostic significance when assessing development of the disease and its severity. Direct detection of their content in the oral fluid makes this method relevant, and potentially demanded for the outpatient diagnostics, being highly important during pandemics of coronavirus infection and limited medical resources. Examination of oral fluid at the pre-hospital stage is a resource-saving technology, since it does not require additional medical staff to take biomaterial, is non-invasive to the patient, and suggesting a wide range of research items, it can resolve a number of diagnostic issues, e.c., presence of specific genetic material or antibodies to SARS-CoV-2, severity of the inflammatory process and the risk of respiratory failure in the patient.

A case of long-term persistence of parvovirus B19 is described for the first time in a patient with Gilbert's syndrome against the background of immunodeficiency with predominance of infectious symptoms (chronic herpesvirus infection). Previously, the patient (male, 48 years old) was diagnosed with Gilbert's syndrome, chronic rhinosinusopharyngitis, and chronic herpesvirus infection. In July 2017, parvovirus B19 DNA was detected in blood. No clinical manifestations of infectious erythema were noted. The patient was admitted to the medical center of St. Petersburg Pasteur Institute. His blood samples obtained under informed consent were examined at the medical center in Central Clinical and Diagnostic Laboratory of St. Petersburg Pasteur Institute in January and June 2018 and in November 2019. ELISA test systems “Anti-Parvovirus B19 ELISA (IgM)” and “Anti-Parvovirus B19 ELISA (IgG)” (Euroimmune, Germany), as well PCR reagent kit “AmpliSens Parvovirus B19-FL” (FSB Central Research Institute of Epidemiology of Rospotrebnadzor, Russia) were used for specific diagnostics. Interferon status was determined by the induced production of IFN types I, II and circulating (serum) interferons. Moreover, we considered the laboratory data obtained earlier at different medical facilities of St. Petersburg. IgM class antibodies to the parvovirus B19 were not detected in the blood samples obtained in 2018. IgG antibody titer was 96 IU/ml and 264 IU /ml, respectively. Parvovirus B19 DNA was isolated from blood plasma, but the viral load was less than 720 IU of PVB19 DNA/ml (1.5 x 10² and 1.9 x 10² copies of DNA/ml, respectively). Clinical blood analysis, showed only minor (no more than 7%) deviations from the reference values, increased hemoglobin saturation of red blood cells (RBC), a decreased width of RBC distribution curve, and relative lymphocytosis. A deficiency of various interferon types was revealed: IFNγ level was 80 IU/ml in both samples, IFNα, IFNβ amounts varied from 80 to 160 IU/ml, respectively. The period of parvovirus B19 DNA persistence in blood was 11 months in presence of immunodeficiency. The patient was administered drugs of the interferon group. Parvovirus B19 DNA was not detected in clinical samples of November 2019; IFNα, IFNβ and IFNγ values were 160 IU/ml. We have detected recovery of lymphoid cell ratio, increase in their number, and improved indexes of interferon status.

We examined expression pattern of CD80 and HLA-DR pro-inflammatory molecules on the monocytes in patients with pulmonary tuberculosis (TB), depending on the clinical form of the disease and susceptibility of the pathogen to anti-tuberculosis drugs. The study involved forty-five patients with newly diagnosed pulmonary TB (25 men and 20 women aged 18 to 55 years, average age — 44.0±12.4 years). The control group included 15 healthy donors with similar socio-demographic characteristics as in TB patients. Venous blood was used as biomaterial for assays. Studies of the monocyte immunophenotype were carried out by flow cytometry of whole blood cells using Cytoflex flow cytometer (Beckman Coulter, USA) with specific monoclonal antibodies (eBioscience, USA). We determined the content of cells expressing surface markers of monocytes, i.e., CD14, CD45, CD80, and HLA-DR. The results of this study were evaluated using SPSS Statistics 17.0 standard software package and Microsoft Excel. In the course of the study, we have suggested a working hypothesis that the monocytes in TB patients, still being in circulation, can express activation markers during their migration to inflammation focus, especially CD80 and HLA-DR molecules. Analysis of the total CD14⁺ monocyte number showed its decrease in all forms and variants of clinical course of pulmonary tuberculosis compared with the control group. Assessment of pro-inflammatory markers expressed on CD14 positive monocytes, i.e., HLA-DR activation marker and CD80 co-stimulatory molecule, showed that the number of monocytes with HLA-DR expression in all TB patients was higher than in healthy donors. HLA- DR expression on CD14⁺ monocytes in the group of patients with infiltrative TB proved to be 15% higher than in patients with disseminated TB. The expression of CD80 on CD14⁺ monocytes in TB patients showed no differences between the groups and varied within the normal range. Hence, an imbalance within monocyte population in patients with pulmonary tuberculosis, regardless of its clinical form and drug sensitivity of the pathogen is developed, due to decrease in total number of CD14⁺ cells, along with increased relative number of monocytes expressing HLA-DR activation marker (pro-inflammatory phenotype). Meanwhile, expression of the CD80 co-stimulatory molecule on monocytes was within normal values.