Broadly Reactive Nanobody Targeting the H3 Hemagglutinin of the Influenza A Virus.

Monoclonal antibodies and recombinant antibody fragments are a very promising therapeutic tool to combat infectious diseases. Due to their unique paratope structure, nanobodies (VHHs) hold several advantages over conventional monoclonal antibodies, especially in relation to viral infections. Influenza A viruses (IAVs) remain a major threat to public health. The hemagglutinin (HA) protein is the main protective and immunodominant antigen of IAVs. In this study, three broadly reactive nanobodies (D9.2, E12.2, and D4.2) to H3N2 influenza strains were isolated and Fc-fusion proteins (VHH-Fcs) were obtained and characterized in vitro. This modification improved the nanobodies' binding activity and allowed for their interaction with a wider range of strains. The D9.2-Fc antibody showed a 100% protection rate against mortality in vivo in a mouse lethal model. Furthermore, we demonstrated that the observed protection has to do with Fc-FcγR interactions. These results indicate that D9.2-Fc can serve as an effective antiviral agent against the H3N2 influenza infection.

Retrospective Analysis of Lipid-Lowering and Antiplatelet Therapy Regimen by Clinical Decision Support Service Based on Real-World Data from Electronic Medical Records "Intellect 3 Study".

Aim      To evaluate prescription of lipid-lowering and antithrombotic therapy in clinical practice and to compare differences in recommendations using the clinical decision support service (CDSS).Material and methods  Electronic medical records (EMR) of 300 patients from the Chazov National Medical Research Center of Cardiology, as well as from medical organizations controlled by the Department of Health of the Lipetsk Region and the Ministry of Health of the Voronezh Region, were analyzed for the period of August - December 2022, during the pilot implementation of CDSS. Retrospective information about the prescription of lipid-lowering and antithrombotic therapy from the EMR was compared with the CDSS guidelines under the expert supervision based on digitized clinical and laboratory profiles of patients. The study primary endpoint was a change in the initially prescribed lipid-lowering and / or antithrombotic therapy as per CDSS guidelines.Results Overall 292 patients were included in the final analysis; 46 (15.7 %) were from the primary prevention group and 246 (84.3 %) from the secondary prevention group. In group 1, the lipid-lowering therapy recommended by the CDSS differed by 50 % (p<0.001) from the baseline therapy recorded in the EMR. In the secondary prevention group, 78.9 % (p<0.001) differences were found in the lipid-lowering therapy recommended in the CDSS guidelines compared to the prescriptions in the EMR. In 76.8 % (p<0.001) of patients, antithrombotic therapy was significantly different from the baseline therapy in the EMR.Conclusion      The use of CDSS may improve the practice of choosing lipid-lowering and antithrombotic therapy for prevention of cardiovascular complications.

Efficacy of the Technologically Processed Antibodies to the Brain-Specific S100 Protein in a Rat Model of Hemorrhagic Stroke.

We studied the ability of technologically processed antibodies to the brain-specific S100 protein (drug Prospekta) to reduce the brain lesion area, neurological disorders, and mortality in a rat model of hemorrhagic stroke. Technologically processed antibodies to S100 exerted a positive effect on all these parameters (brain lesion area, survival rate, neurological status according to the Menzies scale, and proportion of contralateral turns). This allows us to recommend further research into the spectrum of pharmacological activity and the mechanism of action of technologically processed antibodies to S100 in order to expand the indications for their use after the necessary clinical trials.

[DNA Probes for Analysis of the Activity of Key Enzymes of the Base Excision DNA Repair Pathway in Human Cells].

The important role of DNA damage in the occurrence of various diseases, including cancer, has led to study of the mechanisms of genetic information stability, that have been carried out since the discovery of DNA repair systems. The question of the relationship between the accumulation of DNA damage, disorders in DNA repair pathways, and increased risk of disease development is still relevant. Over the past few years, significant efforts have been made to develop methods for analyzing the activity of DNA repair enzymes in human cells. In this work, we developed fluorescent DNA probes that allow us to determine the activity of key enzymes of base excision DNA repair in cell extracts, namely the DNA glycosylases UNG2, SMUG1, MBD4, TDG, AAG, NEIL1, NTHL1, and OGG1 and the AP endonuclease APE1. The sensitivity of DNA probes was determined on pure enzyme preparations. Determination of the activity of repair enzymes in cell extracts of the human ovarian tumor lines TOV112, 79, OVCAR3, MESOV, SCOV3, and TOV21 revealed significant variability in the level of enzyme activity in these cell lines. These results may become a test system platform for analyzing the activity of the base excision DNA repair system in the human body.

Age and Sex Characteristics of the Blood Cytokine Profile in Rats Subjected to Prenatal Stress.

Parameters of blood cytokine profile in male and female rats subjected to prenatal stress on the model of swimming in cold water (10°C, 5 min, days 10-16 of gestation) were studied. Prenatal stress had no significant effects on the blood levels of IL-6 and IL-10 cytokines. The blood concentration of proinflammatory cytokine TNFα in 60-day-old rats was higher than in age-matched controls. Stress led to a lower level of anti-inflammatory IL-4 in the blood of 30-day-old males compared to controls. In female rats subjected to prenatal stress, the concentration of IL-4 decreased on day 21, but increased by day 60 of postnatal ontogeny. Specific effects of prenatal stress on the blood cytokine profile in male and female animals at different periods of ontogeny were revealed. Different and even opposite changes in blood cytokine levels could be largely mediated by sex- and age-specific features of immune functions after prenatal stress.

[Functional heterogeneity of the von Willebrand factor: pathogenetic significance and practical aspects of use in cardiology].

This review focuses on the participation of von Willebrand factor (VWF), that considerably contributes to thrombogenesis in damaged blood vessels, in the pathogenesis of atherosclerosis-induced cardiovascular pathology. Excessive formation and dysfunction of VWF leads to intravascular thrombosis and facilitates the development of endothelial dysfunction, vascular inflammation, and, thereby, the initiation and progression of atherosclerosis. The review presents information based on the analysis of full-text publications from PubMed that address the role of VWF in the development of atherosclerosis and its complications as well as the potential for influencing this index.

[Specific features of the pathology of the respiratory system in SARS-CoV-2 (Coronaviridae: Coronavirinae: Betacoronavirus: Sarbecovirus) infected Syrian hamsters (Mesocricetus auratus)].

INTRODUCTION: Verification of histological changes in respiratory system using Syrian (golden) hamsters (Mesocricetus auratus) as experimental model is an important task for preclinical studies of drugs intended for prevention and treatment of the novel coronavirus infection COVID-19.The aim of this work was to study pathological changes of pulmonary tissue in SARS-CoV-2 (Coronaviridae: Coronavirinae: Betacoronavirus; Sarbecovirus) experimental infection in Syrian hamsters. MATERIAL AND METHODS: Male Syrian hamsters weighting 80-100 g were infected by intranasal administration of culture SARS-CoV-2 at dose 4 × 104 TCID50/ml (TCID is tissue culture infectious dose). Animals were euthanatized on 3, 7 and 14 days after infection, with gravimetric registration. The viral load in lungs was measured using the polymerase chain reaction (PCR). Right lung and trachea tissues were stained with hematoxylin-eosin and according to Mallory. RESULTS AND DISCUSSION: The highest viral replicative activity in lungs was determined 3 days after the infection. After 7 days, on a background of the decrease of the viral load in lungs, a pathologically significant increase of the organ's gravimetric parameters was observed. Within 3 to 14 days post-infection, the lung histologic pattern had been showing the development of inflammation with a succession of infiltrative-proliferative, edematousmacrophagal and fibroblastic changes. It was found that initial changes in respiratory epithelium can proceed without paranecrotic interstitial inflammation, while in the formation of multiple lung parenchyma lesions, damage to the epithelium of bronchioles and acinar ducts can be secondary. The appearance of epithelioid large-cell metaplastic epithelium, forming pseudoacinar structures, was noted as a pathomorphological feature specific to SARS-CoV-2 infection in Syrian hamsters. CONCLUSION: As a result of the study, the specific features of the pathology of the respiratory system in SARSCoV-2 infected Syrian hamsters were described. These findings are of practical importance as reference data that can be used for preclinical studies to assess the effectiveness of vaccines and potential drugs.

Lymphocyte Index of Peripheral Blood in Rats at Different Stages of the Post-Stress Period under Conditions of Antigenic Exposure and Injection of Lipopolysaccharide.

Changes in the Shaganin lymphocyte index (ratio of the number of lymphocytes to segmented neutrophils) in the peripheral blood of rats after intraperitoneal administration of LPS (100 µg/kg) at the end of a single stress exposure in a model of 24-h restraint stress were studied. The lymphocyte index was analyzed 3 h later, on the 1st and 8th days after the stress load. Immobilization was accompanied by a decrease in this parameter 3 h after exposure. One day after the stress load, an increase in the lymphocyte index was noted, which remained on the 8th day of observation. LPS injection did not affect the changes in this parameter caused by 24-h immobilization on the 1st and 8th days of the study, but prevented a pronounced increase in the lymphocyte index on the 1st day after the stress load. The data obtained expand the existing scientific understanding of the specificity of the involvement of immunomodulatory substances in the implementation of adaptive-compensatory processes in mammals under conditions of emotional stress.

Correlation of Physiological Parameters in Rats after Stress Exposure under Conditions of Antigenic Stimulation with Lipopolysaccharide Administration.

We studied correlation dependences between physiological parameters in rats in 3 h, 1 day, and 8 days after administration of LPS (100 µg/kg) at the end of 24-h immobilization stress. In 3 h after LPS administration against the background of stress exposure, significant correlations of metabolic parameters with the relative weight of the adrenal glands and the perceptual component of nociception in rats were revealed. A direct relationship between the concentration of the proinflammatory cytokine TNFα and anti-inflammatory IL-4 was also found in these animals. On the first day after LPS injection, correlations were revealed, predominantly positive, only between the indicators of the cytokine blood profile. In the late post-stress period after antigenic exposure, no correlations between the studied physiological parameters were found. It can be hypothesized that immune modulation through systemic administration of LPS prevents persistent excessive stress of physiological functions at the later stages after stress exposure.

[Comparative Analysis of the Activity of the Polymorphic Variants of Human Uracil-DNA-Glycosylases SMUG1 and MBD4].

The human N-glycosylases SMUG1 and MBD4 catalyze the removal of uracil residues from DNA resulting from cytosine deamination or replication errors. For polymorphic variants of SMUG1 (G90C, P240H, N244S, N248Y) and the MBD4^(cat) catalytic domain (S470L, G507S, R512W, H557D), the structures of enzyme-substrate complexes were obtained by molecular dynamic simulation. It was experimentally found that the SNP variants of SMUG1, N244S and N248Y, had increased catalytic activity compared to the wild-type enzyme, probably due to the acceleration of the dissociation of the enzyme-product complex and an increase in the enzyme turnover rate. All other SNP variants of SMUG1 (G90C, P240H) and MBD4^(cat), in which amino acid substitutions disrupted the substrate binding region and/or active site, had significantly lower catalytic activity than the wild-type enzymes.

Clinical Characteristics and Factors Associated with Poor Outcomes in Hospitalized Patients with Novel Coronavirus Infection COVID-19.

Aim      To evaluate the clinical picture and factors associated with unfavorable outcomes in admitted patients with COVID-19.Material and methods This study included all patients admitted to the COVID Center of the National Research Center of Cardiology of the Russian Ministry of Health Care from May 1 through May 31, 2020. Clinical demographic, laboratory, and instrumental indexes and associated factors were studied with one-way and multivariate logistic regression analysis.Results This study included 402 patients aged 18 to 95 years (mean age, 62.9±14.6 years); 43.0 % of them were older than 65 years. COVID-19 was frequently associated with chronic comorbidities, including arterial hypertension (74.4 %), obesity (41.6 %), history of ischemic heart disease (12.9 %), atrial fibrillation (18.9 %), type 2 diabetes mellitus (DM) (13.0 %), and oncological diseases (9.2 %). 13.0 % of patients were smokers; less than 10% had chronic lung diseases. 3.9% of patients had a combination of COVID-19 and acute coronary pathology, including acute myocardial infarction (MI) in 3.2 % (13) and unstable angina in 0.7 % (3). The most frequent clinical manifestation of COVID-19 were four symptoms: cough (81.1 %), weakness (80.3 %), shortness of breath (71.6 %), and fever (62.7 %). 46.5% of patients had shortage of breath and chest pain/compression, 40.3% had headache, 31.1% had myalgia, 28.8% had anosmia, and 25.5% had ageusia. Arterial oxygen saturation was <93.0 % in 55.7 % of cases. According to laboratory blood tests the patients had anemia (58.2 %), lymphopenia (34.8 %), neutropenia (19.2 %), thrombocytopenia (11.9 %), and increased levels of high-sensitivity C-reactive protein (hsCRP, 87.3 %), interleukin-6 (89.3 %), ferritin (62.1 %), and D-dimer (49.2 %). 56.2% of patients required various regimens of oxygen support. 83 (20.6%) patients were admitted to intensive care and resuscitation units; invasive artificial ventilation was performed only for 34 (8.5 %) patients. In-hospital mortality was 7.7 % (31 / 402). One-way regression analysis identified major factors associated with death during the stay in the hospital: age >55 years, NEWS scale score >4.0, oxygen saturation <92.0 %, blood glucose >5.4 mmol/l, hs-CRP >25.7 mg/l, and creatinine clearance <72.0 ml/min. Furthermore, the risk increased with increasing degree of changes in each factor. According to results of the multivariate regression analysis, three most significant predictors of the hard endpoint, all-cause death during the stay in the hospital, were more than 5-fold increases in aspartate aminotransferase and/or alanine aminotransferase compared to normal levels (relative risk (RR) 16.8 at 95 % confidence interval (CI) 5.0-56.3, р<0.001), pronounced changes in the lungs consistent with a CT-4 picture as shown by computed tomography (CT) (RR 13.4; 95 % CI 3.9-45.5, р<0.001), and MI/unstable angina during the stay in the hospital (RR 11.3; 95 % CI 1.4-90.6, р=0.023). The probability of death was also considerably increased by chronic obstructive pulmonary disease, impaired kidney function (creatinine clearance estimated by Cockcroft-Gault <60.0 ml/min), type 2 DM, oncological diseases, and dementia.Conclusion      This study established factors associated with unfavorable outcomes in admitted patients with COVID-19. This will allow identifying in advance patients with a high risk of complications that require increased attention to take more active diagnostic and therapeutic measures at prehospital and hospital stages.

The role of active-site amino acid residues in the cleavage of DNA and RNA substrates by human apurinic/apyrimidinic endonuclease APE1.

BACKGROUND: Human apurinic/apyrimidinic endonuclease APE1 is one of participants of the DNA base excision repair pathway. APE1 processes AP-sites and many other types of DNA damage via hydrolysis of the phosphodiester bond on the 5' side of the lesion. APE1 also acts as an endoribonuclease, i.e., can cleave undamaged RNA. METHODS: Using pre-steady-state kinetic analysis we examined the role of certain catalytically important amino acids in APE1 enzymatic pathway and described their involvement in the mechanism of the target nucleotide recognition. RESULTS: Comparative analysis of the cleavage efficiency of damaged DNAs containing an abasic site, 5,6-dihydrouridine, or α-anomer of adenosine as well as 3'-5'-exonuclease degradation of undamaged DNA and endonuclease hydrolysis of RNA substrates by mutant APE1 enzymes containing a substitution of an active-site amino acid residue (D210N, N212A, T268D, M270A, or D308A) was performed. Detailed pre-steady-state kinetics of conformational changes of the enzyme and of DNA substrate molecules during recognition and cleavage of the abasic site were studied. CONCLUSIONS: It was revealed that substitution T268D significantly disturbed initial DNA binding, whereas Asn212 is critical for the DNA-bending stage and catalysis. Substitution D210N increased the binding efficacy and blocked the catalytic reaction, but D308A decreased the binding efficacy owing to disruption of Mg2+ coordination. Finally, the substitution of Met270 also destabilized the enzyme-substrate complex but did not affect the catalytic reaction. SIGNIFICANCE: It was found that the tested substitutions of the active-site amino acid residues affected different stages of the complex formation process as well as the catalytic reaction.

Role of Arg243 and His239 Residues in the Recognition of Damaged Nucleotides by Human Uracil-DNA Glycosylase SMUG1.

Human uracil-DNA glycosylase SMUG1 removes uracil residues and some other noncanonical or damaged bases from DNA. Despite the functional importance of this enzyme, its X-ray structure is still unavailable. Previously, we performed homology modeling of human SMUG1 structure and suggested the roles of some amino acid residues in the recognition of damaged nucleotides and their removal from DNA. In this study, we investigated the kinetics of conformational transitions in the protein and in various DNA substrates during enzymatic catalysis using the stopped-flow method based on changes in the fluorescence intensity of enzyme's tryptophan residues and 2-aminopurine in DNA or fluorescence resonance energy transfer (FRET) between fluorophores in DNA. The kinetic mechanism of interactions between reaction intermediates was identified, and kinetic parameters of the intermediate formation and dissociation were calculated. The obtained data help in elucidating the functions of His239 and Arg243 residues in the recognition and removal of damaged nucleotides by SMUG1.

Blood Cytokine Concentration in Rats during Antigenic Treatment after a Single Long-Term Stress Exposure.

We studied changes in the blood cytokine profile of rats 3 h, 1 day, and 8 days after acute stress on the model of 24-h immobilization followed by LPS administration (100 µg/kg intraperitoneally). The concentration of proinflammatory cytokines (particularly of IL-1ß and TNFα) significantly decreased at the early stage after stress exposure and physiological saline injection, but increased in the follow-up period and practically did not differ or even surpassed the control level by the end of observations. Under these conditions, the blood content of anti-inflammatory cytokine IL-10 increased most significantly on day 1 of the post-stress period. Restraint stress followed by LPS administration was accompanied by a decrease in the level of proinflammatory cytokines at the early (IFNγ and TNFα) and late stages (IL-1ß) of the experiment. Directed modulation of the immune status in animals after acute stress was followed by a significant increase in the content of IL-10 on days 1 and 8, as well as by a tendency toward elevation of IL-4 concentration by the end of the study. The directionality and degree of changes in the cytokine profile of mammalian tissues depend on the type of extreme exposure, duration of the post-stress period, and specific effects of exogenous pathogenic factors in the whole body.

Mechanisms of Pulmonary Toxicity of Perfluoro-n-Alkane Pyrolysis Products with Consideration of the Structural Features of the Blood-Air Barriers.

Perfluoroisobutylene a is pulmonotoxic chemical generated during pyrolysis of perfluoro-nalkanes (polytetrafluoroethylene). The mechanisms of acute pulmonary toxicity induced by perfluoroisobutylene have not been studied yet. The analysis of tissues of brown frogs showed that the products of polytetrafluoroethylene pyrolysis induce typical inflammatory response in the lungs (fluid accumulation, erythrocyte stasis, desquamation of the epithelium, and capillary plethora in lung septa) and oropharyngeal cavity (degeneration of ciliated epithelium, hyperemia of underlying vessels with plasmatic imbibition of the connective tissue, and margination of segmented leukocytes and monocytes). The absence of surfactant is a specific feature of the blood-air barrier of the oropharyngeal cavity in frogs compared to the lungs. It can be hypothesized that toxic effects of perfluoroisobutylene are determined by its influence on epithelial (pneumocytes and cells of nonkeratinized stratified ciliated epithelium) and endothelial cells. Even though the effects of the agent on surfactant cannot be excluded, they do not determine the probability of development of inflammatory response.

[The Diagnostic Accuracy of Exercise Treadmill Testing and Stress Echocardiography for the Detection of Obstructive Coronary Artery Disease in Patients Aged ≥ 70 Years].

AIM: to compare diagnostic accuracy of exercise treadmill testing and stress echocardiography in the diagnosis of stable coronary artery disease (CAD) in patients aged >70 years. MATERIALS AND METHODS: The study included 390 patients aged >70 years with suspected stable ischemic heart disease, who underwent elective coronary artery angiography (CAG). Exercise treadmill testing (ETT) according to the modified Bruce protocol was carried out in 189 patients (48 %), bicycle stress echocardiography - in 179 patients (46 %). Initially we determined the prevalence of angiographically significant CAD according to the gender and chest pain character, and identified persons in whom stress testing was appropriate. After that diagnostic accuracy of both tests was evaluated in patients with atypical angina and non-anginal chest pain. RESULTS: Among 72 patients with atypical angina and non-anginal pain who underwent ETT and had unequivocal results, 38 (53 %) had obstructive CAD. ETT for detection of obstructive CAD had sensitivity 79 %, specificity 82 %, positive likelihood ratio (LR+) 4.4, and negative likelihood ratio (LR-) 0.3. Positive result increased probability of obstructive CAD from 53 % to 83 %, negative result reduced probability of obstructive CAD to 25 %. Among 111 patients with atypical angina and non-anginal pain who underwent stress echocardiography and had unequivocal results, 69 (62 %) had obstructive CAD. Sensitivity, specificity, LR+, and LR- of stress echocardiography were equal to 89 %, 95 %, 17.8, and 0.1, respectively. Positive result increased probability of obstructive CAD from 62 % to 95 %, negative result reduced probability of obstructive CAD to 16 %. CONCLUSION: bicycle stress echocardiography was found to be more accurate than ETT to rule in or rule out obstructive CAD in patients aged ≥ 70 years with atypical angina and non-anginal pain.

State of Stress-Marker Organs in Rats after a Single Exposure to Long-Term Stress and Treatment with Lipopolysaccharide.

We studied the effect of LPS on the state of stress-marker organs in rats at various periods after a single exposure to long-term stress on the model of 24-h immobilization. The animals were intraperitoneally injected with LPS in a dose of 100 µg/kg immediately after the negative emotiogenic exposure. Changes in physiological parameters were evaluated 3 h, 1 day, and 8 days after immune stimulation. Acute stress was accompanied by a decrease in the weight of the thymus during all stages of the post-stress period. An increase in the relative weight of theadrenal glands in animals under these conditions was observed only on day 8 after restraint stress. The induction of immune reactions due to systemic treatment with LPS was shown to prevent involution of the spleen in the late stage after a single exposure to long-term stress (day 8). Hypertrophy of the adrenal glands, which serves as one of the typical reactions of mammals to negative emotiogenic factors, was not revealed during the post-stress period after antigenic stimulation. These data hold much promise for the development of new approaches to the use of immunoactive substances to prevent or reduce the severity of physiological changes after emotiogenic loads.

Passive Q-switching of an Er, Yb:glass laser with Co:Mg(Al,Ga)2O4-based glass-ceramics.

Transparent glass-ceramics (GCs) containing Co:Mg(Al,Ga)2O4 nanocrystals (mean diameter of 7-9 nm) are synthesized by heat treatments at 850-950°C from magnesium aluminosilicate glass nucleated by TiO2 and doped with Ga2O3 and CoO. The GCs exhibit a broadband A24(F4)→T14(F4) absorption due to the Co2+ ions, low saturation fluence (∼0.5 J/cm2), fast recovery time of initial absorption (∼300 ns), and high laser damage threshold (∼20 J/cm2). They are used for passive Q-switching of a diode side-pumped Er,Yb:glass laser generating 3.1 mJ/20 ns pulses (peak power, 155 kW) at 1535 nm with a TEM00 output mode. The Q-switching performance of the Co:Mg(Al,Ga)2O4-based GCs is compared with that for various Co2+-doped GCs and Co:MgAl2O4 single crystal. The prepared GCs are promising for further applications in passively Q-switched Er:YAG and other Er crystalline (or ceramic) lasers.

[DYNAMICS OF CYTOKINE CONCENTRATION IN THE BLOOD OF RATS WITH VARIOUS BEHAVIORAL CHARACTERISTICS AFTER ACUTE EMOTIONAL STRESS].

This work was designed to study a change in cytokine content in the peripheral blood of behaviorally passive and active Wistar rats at various time intervals after acute stress on the model of night-time immobilization. A decrease in the concentration of most pro- and anti-inflammatory cytokines in passive animals was most pronounced immediately and, particularly, 3 days after stress exposure. Variations in the blood cytokine profile after experimental stress were lower in behaviorally active specimens. A statistically significant decrease was observed only in the amount of a proinflammatory cytokine IL-1α and anti-inflammatory cytokines IL-4 and IL-13. As differentiated from passive rats, these changes in active specimens were most pronounced 1 day after negative emotiogenic exposure. Our results illustrate a specific involvement of immunoactive substances in the systemic regulation of physiological functions and development of individual resistance to the negative consequences of stress.

[Effect of minor bioactive food substances ­ rutin and hesperidin in their separate and combined alimentary arrives on the immune system of rats and the activity of nuclear factor NF-kB liver cells].

The effect of rutin and hesperidin in their separate and combined admission to the immune system and the activity of nuclear factor NF-kB of rat liver cells has been investigated. Wistar male rats with an initial body weight of 224­225 g were divided into 4 groups of 6 rats in each. The rats of the 1st group (control) received a complete semi-synthetic diet, rats in group 2 ­ the same diet supplemented with rutine (400 mg/kg b.w.); the rats of group 3 ­ with the addition of hesperidin (400 mg/kg bw); group 4 ­ with the addition of rutin and hesperidin (400 mg/kg b.w. each) for 14 days. Animals received feed in free access mode in an amount of 25­30 g per rat per day, that corresponded to 15 g of dry formula. Animals received water also in free access. It has been found that rutin and hesperidin, included in the diet of rats both alone (groups 2 and 3) and together (group 4), have immunomodulatory impact which is a reduce of lymphocyte relative content [1st gr. ­ 70.55±1.58%, 2nd gr. ­ 63.62±2.85%, 3rd gr. ­ 62.03±3.16% (p1­3<0.05), 4th gr. ­ 65.75±1.08% (p1­4<0.05)] and an increase of percentage of neutrophil leukocytes [1st gr ­ 19.98±0.97%, 2nd gr. ­ 25.35±3.14%, 3rd gr. ­ 28.27±3.30% (p1­3<0.05), 4th gr. ­ 24.15±1.52% (p1­4<0.05)] and NK-cells in the peripheral blood [1st gr. ­ 3.29±0.45%, 2nd gr. ­ 6.91±0.70% (p1­2<0.05), 3rd gr. ­ 5.88±0.79% (p1­3<0.05), 4th gr. ­ 4.64±0.32% (p1­4<0.05)], that can be considered as a shift in the direction of innate immunity factors. In addition, the combined effect of high doses of rutin and hesperidin led to a change in erythrocyte parameters: an increase in the average volume of red blood cells [1st gr. ­ 56.00±1.06 fl, 2nd gr. ­ 56.67±0.42 fl, 3rd gr. ­ 58.50± 0.99 fl, 4th gr. ­ 59.50±0.99 fl (p1­4<0.05)], and the average content of hemoglobin [1st gr. ­ 18.97±0.45 pg, 2nd gr. ­ 19.10±0.19 pg, 3rd gr. ­ 19.73± 0.32 pg, 4th gr. ­ 20.08±0.33 pg (p1­4=0.07)], as well as increase in the level of TGF-ß1 in peripheral blood [1st gr. ­ 15.55±2.13 ng/ml, 2nd gr. ­ 14.81± 2.36 ng/ml, 3rd gr. ­ 17.02±2.53 ng/ml, 4th gr. ­ 22.14±2.29 ng/ml (p1­4<0.05)] and the expression of nuclear factor NF-kB in the liver cells [1st gr. ­ 16.10± 0.60 ng/ml; 2nd gr. ­ 15.14±2.28 ng/ml; 3rd gr. ­ 15.85±2.09 ng/ml; 4th gr. ­ 20.49±1.68 ng/ml (p1­4<0.05)].