Sarcoidosis is a systemic inflammatory disease of unknown etiology, characterized by the formation of epithelioid cell granulomas, multisystem lesions with a certain frequency of involvement of various organs, mainly the lungs (up to 90% of cases). Over the past decade, significant progress has been made in understanding the pathogenesis of sarcoidosis, the important role of immunological, genetic and environmental factors in the development of this pathology has been established. It is believed that the leading mechanism in the pathogenesis of sarcoidosis is the aberrant activation of the innate and adaptive immune response to unidentified antigen(s), which leads to the development of granulomatous inflammation and the formation of granulomas. However, despite the huge number of studies that has been carried out, the mechanisms and signaling pathways that control the development of the inflammatory process during the formation of granulomas and the progression of pathology have not been fully determined.This literature review examines the important role of various cytokines and T helper subpopulations in sarcoidosis. Particular attention is paid to the cells of innate immunity – macrophages in the pathogenesis of this disease. These cells play a key role in the formation of sarcoid granulomas and in the pathogenesis of sarcoidosis. The macrophage population is characterized by plasticity and functional heterogeneity. In response to various signals from the microenvironment, macrophages are able to acquire certain phenotypes. The review considers the issues of polarization of macrophages, changes in the phenotype of these cells to subpopulations M1 (M1 phenotype; classically activated; pro-inflammatory) and M2 (M2 phenotype; alternatively activated, anti-inflammatory). These two cell populations are characterized by the expression of different markers on their surface, which allow these cells to differentiate from each other. The analysis of literature data on the levels of key polarizing cytokines for macrophages and cells-producers of these cytokines that patients with sarcoidosis have, in acute and chronic course of the disease, was carried out.Important aspects of the alternative activation of macrophages of the M2 phenotype and their division into subtypes: M2a, M2b, M2c, M2d are noted. The features of various subtypes’ activation of macrophages in this granulomatosis and their importance in the development and progression of pathology are considered. Studying the role of macrophages’ phenotypes, understanding the mechanisms by which the phenotypes of these cells are activated and modulated in various microenvironmental conditions, can contribute to the development and implementation into clinical practice of new therapeutic approaches for the treatment of sarcoidosis and many other forms of pathologies.

The lipopolysaccharide (LPS)-induced inflammation model is widely used in mammalian studies but remains poorly investigated in a variety of fish species. We reproduce this model in rainbow trout, Oncorhynchus mykiss, a species of high economic value, to validate specific inflammatory biomarkers for reliably assessing the health and immune status of farmed fish. The inflammatory process, together with the effect of preconditioning, was modeled using two consecutive intraperitoneal injections of 300 and 600 µg LPS. We assessed innate immunity biomarkers, including the expression of inflammation-related genes (il1ß, il8), peripheral blood leukocyte profiles, serum bactericidal activity (SBA), and various serum and hepatic biochemical parameters. These parameters comprised the concentration of C-reactive protein (CRP, an acute phase protein), and the activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione-S-transferase) measured at 24 and 96 h post-injection. In trout, LPS-induced effects involved the overexpression of pro-inflammatory interleukins (il1ß, il8), a left shift in white blood cells (characterized by a prevalence of immature neutrophils), and enhanced SBA. In contrast to warm-blooded animals, LPS challenge in trout did not appear to significantly elevate CRP levels or antioxidant enzyme activity. Further investigations in other fish species are needed to determine whether these are traits specific to trout or common to bony fish. Our findings provide a foundation for developing a biomarker panel suitable for the routine assessment of welfare, early detection of infection-associated inflammation in cultured fish, and the screening of the anti-inflammatory and immunostimulant activities of drugs and feed additives.

The protein composition of the cestode Schistocephalus solidus was measured in an experiment simulating the trophic transmission of the parasite from a cold-blooded to a warm-blooded host. The first hour of host colonisation was studied in a model experiment, in which sticklebacks Gasterosteus aculeatus infected with S. solidus were heated at 40°C for 1 h. As a result, a decrease in the content of one tegument protein was detected in the plerocercoids of S. solidus. Sexual maturation of the parasites was initiated in an experiment where S. solidus larvae were taken from fish and cultured in vitro at 40°C for 48 h. Temperature-independent changes in the parasite proteome were investigated by incubating plerocercoids at 22°C for 48 h in culture medium. Analysis of the proteome allowed us to distinguish the temperature-induced genes of S. solidus, as well as to specify the molecular markers of the plerocercoid and adult worms. The main conclusion of the study is that the key enzymes of long-term metabolic changes (glycogen consumption, protein production, etc.) in parasites during colonisation of a warm-blooded host are induced by temperature.

Recently, more and more attention has been paid to the study of the role of epigenetic mechanisms in the development and progression of immunoinflammatory diseases accompanied by the development of fibrosis. Epigenetic modifications, compared with genetic changes that persist throughout the life of an organism, are extremely dynamic and can differ both in different cell populations and in the same cell depending on the stage of differentiation and microenvironment. The review summarizes information on the potential role of key epigenetic factors, in particular, noncoding RNAs, in the differentiation of circulating bone-marrow-derived monocytes into myofibroblasts, cellular mediators of fibrosis. Owing to their high plasticity and ability for phenotypic transformation, monocytes and macrophages are the most important participants in tissue homeostasis and play a key role in the development of fibrosis at all stages of tissue repair, from inflammation to remodeling.

Aim. To investigate the association of the polymorphic marker -3279 C>A of the FOXP3 gene with the risk of pulmonary sarcoidosis (PS) and to estimate the transcription level of this gene in the carriers of different genotypes of this polymorphic marker. Subjects and methods. The investigation included 99 patients of Russian ethnicity (mean age, 45.41±1.31 years) living in the Republic of Karelia, who were diagnosed with persistent PS, and 116 healthy donors (mean age, 42.06±1.30 years) in the control group. The alleles and genotypes of the polymorphic marker -3279 C>A of the FOXP3 gene were identified using polymerase chain reaction (PCR)-restriction fragment length polymorphism. The number of transcripts of the studied gene in the peripheral blood leukocytes of healthy donors and PS patients was determined with real-time PCR. Results. The control group and the PS patient one had no statistically significant differences in the distribution of the frequencies of alleles and genotypes by the polymorphic marker –308G>A of the FOXP3 gene (p > 0.05). The number of FOXP3 gene transcripts was not statistically significantly different in the peripheral blood leukocytes of patients with PS and control individuals. No statistically significant differences were observed in the mRNA expression levels in the above-mentioned gene in the carriers of different genotypes by the polymorphic marker -3279 C>A of the FOXP3 gene in all examined groups. Conclusion. The polymorphic marker -3279 C>A of the FOXP3 gene is unassociated with the risk of PS.

Objective. The aim of the study was to evaluate the level of expression of the NOS2, NOS3, SONE genes in peripheral blood leukocytes (PBL) of patients with hypertension (HTN) and to study the relationship between the level of transcripts of these genes and the content of nitric oxide metabolites and markers of endothelial dysfunction.Design and methods. The study included healthy people (25 people) and patients with HTN (stages I–II) before prescribing antihypertensive drugs (15 people) and taking cardioselective β-adrenergic receptor blockers for more than a year (metoprolol (25 mg per day) or bisoprolol (5–10 mg per day)) (20 people). The level of gene transcripts was assessed by real-time polymerase chain reaction (PCR). The level of nitric oxide metabolites was determined by the colorimetric method using the Griess reagent. The content of asymmetric dimethylarginine (ADMA), soluble forms of vascular cell adhesion molecule (sVCAM), and intercellular adhesion molecule (sICAM) in blood plasma was determined by ELISA. The content of malondialdehyde (MDA) in blood plasma was determined spectrophotometrically by color reaction with thiobarbituric acid. Statistical processing of the results was carried out using the Statgraphics Centurion XVI software package (version 16.1.11).Results. The level of nitric oxide metabolites in the blood plasma of HTN patients without antihypertensive therapy was 2,1 times higher than in healthy individuals (p = 0,001) and 1,7 times higher than in patients with HTN taking metoprolol or bisoprolol (p = 0,002). The relative content of mRNA of the NOS3 gene in PBL of individuals included in the study did not differ (p > 0,05). The level of NOS2 gene transcripts in PBL of HTN patients before the prescription of antihypertensive drugs exceeded that in healthy individuals (p = 0,0009) and in HTN patients taking metoprolol or bisoprolol (p = 0,0002). The number of SONE transcripts in the PBL of HTN patients was higher than in people with normal blood pressure (p < 0,00001 when comparing patients before the prescription of antihypertensive therapy and individuals from the control group; p = 0,04 when comparing patients with HTN taking antihypertensive drugs and normotensive subjects). The content of MDA, ADMA, sVCAM was higher in the plasma of HTN patients without antihypertensive therapy compared with people from the control group (p = 0,005, 0,003, 0,039, respectively) and patients taking metoprolol or bisoprolol (p = 0,0006, 0,019, 0,016, respectively). The content of nitric oxide metabolites positively correlated with NOS2, SONE, VCAM1 mRNA level in PBL, the content of MDA and ADMA in blood plasma (p < 0,05). A positive correlation was found between the concentration of MDA and ADMA in plasma (p = 0,03).Conclusions. An increase in the level of nitric oxide metabolites in HTN is associated with an increase in the transcriptional activity of the NOS2 gene, a disturbance of the redox balance of the body, and the development of endothelial dysfunction. The SONE gene is probably involved in the modulation of nitric oxide levels in HTN not only as an antisense transcript that destabilizes the mRNA of the NOS3 gene in vascular endothelial cells, but also indirectly, namely, through the regulation of homeostasis of immune system cells through autophagy.