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Postischemic neuroinflammation is a critical pathophysiological process within the entire pattern of cerebral ischemia. It is characterized by microglial and astroglial activation and is accompanied by disturbances in the innate and adaptive immune response. The early damage of the blood-brain barrier (BBB) integrity is accompanied by the brain autoantigens release into circulation, in particular, the neurospecific protein S100B. According to recent experimental data, activated autophagy is associated with postischemic neuroinflammation, involved in its regulation and influences the outcome of the ischemic stroke (IS) acute period. Experimental evidence is provided for the autophagy involvement in the regulation of proinflammatory cytokines and chemokines production. The influence of activated autophagy on the pro- and anti-inflammatory cytokines balance in acute IS has been demonstrated. Purpose of the study: to quantitatively evaluate key autophagy biomarkers, the early biomarker of BBB damage S100B, pro- and anti-inflammatory cytokines in the dynamics of the IS acute period. To identify the relationship between autophagy and inflammation biomarkers, 112 patients with acute IS and 56 healthy persons were examined. Patients underwent dynamic clinical neurological examination and blood testing on the 1st, 7th and 14th days from the disease’s onset. The level of autophagy in peripheral blood leukocytes was determined by flow cytometry by assessing the intracellular expression of autophagy proteins LC3, p62 and mean fluorescence intensity of the Cyto-ID dye, which specifically recognizes active autophagosomes. Serum concentrations of TNFα, IL-1β, IL-4, IL-6, IL-8, IL-10, IL-18, neuropeptide S100B and autophagy biomarkers Beclin-1, LC3, p62 were determined by ELISA. A statistically significant increase in the studied biomarkers was found compared to the control group. The maximum increase in inflammation indicators and neuropeptide S100B was observed on the 1st, and autophagy biomarkers – on the 7th day of the disease. Established correlations indicate the participation of activated autophagy in the postischemic neuroinflammation regulation and its involvement in ischemic brain damage in the early stages of the IS acute period (days 1-7).

The postischemic inflammatory response plays a significant role in the pathogenesis of acute ischemic stroke (IS). It has been established that acute IS is accompanied by aseptic inflammation, which induces the activation of costimulatory molecules in the process of innate immunity response to brain tissue damage. The constantly progressive destruction of neuronal antigens contributes to an increase in the volume of the ischemic lesion. Evidence continues to accumulate indicating an important role of NLRP3-mediated inflammation in the pathogenesis of IS. It has been shown that autophagy is involved in the inflammatory cascade in acute IS. Many of the anti-inflammatory mechanisms mediated by autophagy in acute IS involve the key autophagic proteins Beclin-1, LC3, and p62. Experimental studies have shown that autophagy suppresses the activation of NLRP3 inflammation. Data on cross interactions between apoptosis and autophagy in the pathogenesis of IS are still controversial. The aim of the study was to evaluate the relationship between biomarkers of autophagy, inflammation, and apoptosis in the dynamics of the acute period of atherothrombotic IS. The article presents the results of a dynamic study of the serum concentration of the key autophagy biomarkers Beclin-1, LC3 and p62, apoptosis indicators Bcl-2 and p53, pro-inflammatory cytokines IL-1β, TNFα, IL-8, IL-18 which are involved in postischemic neuroinflammation. A statistically significant increase in the studied parameters was established in comparison with the control group. The maximum increase in the studied biomarkers is noted on the 1st day after the development of ischemia in patients with a severe course of the disease. The relationship between autophagy activity, apoptosis biomarkers, and some indicators of the systemic inflammatory response in patients with moderate and severe atherothrombotic stroke was revealed. The results obtained confirm the literature data on the involvement of autophagy in the regulation of the postischemic inflammatory response.

Assessment of viral load levels in various biological samples taken from the respiratory tract can be an indicator of an ongoing process of active viral replication and may be used to monitor severe respiratory viral infections. The study of the relationship between SARS-CoV-2 viral load and immunological laboratory parameters is an important step in the search for clinical markers of COVID-19.The aim of this research was to quantify viral load in patients with COVID-19 and to identify the relation-ship between viral load and changes in the parameters of the cellular component of the immune system.A laboratory examination was carried out on 74 patients diagnosed with COVID-19, they were divided into 3 groups based on the severity of the disease: mild, moderate, severe. Total viral load in clinical samples was determined by the number of SARS-CoV-2 RNA copies per 100 copies of the reference RNaseP gene. A comprehensive assessment of the cellular component of the immune system was performed using flow cytometry and direct monoclonal antibodies, and the IL-6, and C-reactive protein concentrations were determined.We revealed a relationship between the development of serious clinical conditions in the patients with COVID-19, and the levels of viral load. High levels of viral RNA in biological samples correlate with main indicators of the T cell component of the immune system associated with disease severity. In a subgroup of patients with an extremely high viral load, strong positive correlations were found between the relative numbers of cytotoxic lymphocytes (CD3+CD8+), activated T lymphocytes (CD3+HLA-DR+), as well as absolute and relative numbers of activated B lymphocytes and NK cells (CD3-CD25+).Laboratory monitoring of the cellular component of the immune system, along with the assessment of viral loads, should improve early assessment of clinical condition in the patients with COVID-19. Changes in expression levels of activation markers on immune cells can be potentially viewed as indicators of recovery during COVID-19.

To date, there is no consensus explaining the relationship between varying concentrations of IFNγ and the severity of infection caused by SARS-CoV-2. The aim of this article was to analyze and formulate conclusions from the selected studies and publications, which, in sum, provide a potentially reasonable view on the role of IFNγ in COVID-19 pathogenesis. This article highlights current data on the immunological role of IFNγ which affects differentiation of naive T helper cells, acting as a polarizing factor. It activates the major histocompatibility complex (MHC) class I and II, by increasing the expression of MHC I/II subunits, inhibiting replication of the viral particles by initiating activation of interferon-stimulated genes followed by subsequent synthesis of antiviral proteins. Moreover, IFNγ activates the production of cytokines by T cells, enhancing cytotoxic activity of the T killers. IFNγ exerts immunostimulatory and immunomodulatory effects via STAT1, SOCS1 and PIAS genes, thus regulating activation of the JAK-STAT signaling pathway. A number of studies were considered where the patterns of changes in serum IFNγ concentration were examined in viral infections and SARS-CoV-2. We performed a systemic analysis of the results of studies that showed a relationship between high concentrations of IFNγ and COVID-19 severity. In a number of studies, the significantly high levels of IFNγ in COVID-19 patients were often associated with a poor outcome of the disease. The median values of the IFNγ concentration in severe COVID-19 were found to be significantly higher compared to the results obtained in the cases of moderate severity. It shows an increase, in parallel with viral load in the nasopharyngeal samples upon worsening of the clinical condition. Based on the data on the decreased IFNγ concentrations in convalescent patients, the mechanism of antagonism between IFNγ and IL-4 is considered, where the decreases serum concentrations of IFNγ along with increasing level of IL-4 may be an indirect proof of normal adaptive immune response with subsequent development of antibodies to SARS-CoV-2 and gradual elimination of the virus from the body. Moreover, the evidence is discussed that the patients harboring some parasitic infections (Toxoplasma gondii, Cryptosporidium, Blastocystis hominis, Giardia duodenalis, Entamoeba histolytica) with persistently elevated level of IFNγ are at reduced risk for severe course of COVID-19.

Aim: to evaluate the efficacy and safety of convalescent plasma therapy for patients with severe SARS-CoV-2 infection.Materials and methods: the study included 64 patients with laboratory-confirmed severe new coronavirus infection. The control group consisted of 58 patients who, in addition to standard therapy, received a transfusion of plasma from donors who had recovered from COVID-19. The effectiveness of immune plasma was assessed by the duration of fever, the level of oxygen (SpO2 %) in dynamics, the detection of SARSCoV-2 RNA in nasopharyngeal and oropharyngeal swabs using PCR method in dynamics, as well as by the dynamics of blood tests results. Adverse events (any medically adverse events that occurred after immune plasma transfusion) were recorded as safety criteria.Results: patients who received convalescent plasma, showed a significantly shorter period of SARS-CoV-2 replication compared with the control group. The use of immune plasma did not have a statistically significant effect on the duration of the fever, as well as the dynamics of blood oxygenation. Also, there were no significant differences compared with the control group when assessing blood tests parameters.Conclusion: The use of COVID-19 convalescent plasma to treat severe COVID-19 did not show significant clinical effect but reduced the period of viral replication. It also showed no unexpected or serious adverse events.

Despite continuous attempts to improve therapy, the outcomes of acute myeloid leukemia remain almost unchanged over last decades. Drugs made with a more complete understanding of the biology of acute myeloid leukemia do not equal the hopes for better prognosis. The best results are achieved only with high-dose chemotherapy, which is only possible for a limited number of patients. High phenotypic and genotypic heterogeneity of acute myeloid leukemia defines the relevance to develop personalized approaches to therapy, including those based on determination of individual drug sensitivity of blast cells.This article presents the results of developing an ex-vivo model of acute myeloid leukemia, as well as testing of two in vitro sensitivity assessment methods: evaluation of the genotoxicity of drugs in the micronucleus test and vitality and sensitivity to chemotherapy in sorted blast cells. Prospects of individualized therapy of acute myeloid leukemia were determined based on introduction into clinical practice and continuing the research.

The aim of the research was to study the features of the structure of low-fat butter and butter pastes, which, in terms of composition and properties, more fully meet the requirements of a healthy diet than high-fat types of butter. The objects of research were: butter with fat content of 72.5%; butter with fat content of 55% made with the addition of skimmed milk powder; butter of the same fat content with the addition of stabilizers based on guar and xanthan gums and emulsifiers based on monoand diglycerides of fatty acids; butter pastes with fat content of 45% with similar additives used to increase the stability of the process of butter formation and improve the texture. The microstructure was studied using an MBI-6 microscope, and the ultramicrostructure was studied using a Phillips electron microscope. In the first case, the sample was prepared by crushing the sample, in the second one — by the method of ultrafast freeze-fracture and etching. Researches have shown that the use of the introduced ingredients improves the homogeneity of the structure of the studied products. Due to the ability of milk proteins and stabilizers to retain moisture, it is more evenly distributed and well retained in the fat matrix of the product, formed from crystalline and liquid fat in the form of a continuous phase, which is confirmed by a sufficient penetration depth of the fat-soluble dye. Plasma droplets in butter with fat content of 72.5% and 55% are more isolated than in butter pastes, as indicated by the greater penetration depth of the water-soluble dye. The average diameter of isolated moisture droplets in low-fat products was 3.3–5.4 μm, and the average diameter of the fat globules that form the basis of the crystalline framework was 5.4–7.4 μm, depending on the composition of the product. For butter with fat content of 72.5%, the values of these indicators were 2.8 and 4.0 μm. The results of the study indicate the presence of differences in the sizes of structural elements, but at the same time confirm the uniformity of the structure of low-fat products, allowing them to be attributed to dispersions «water-in-oil».