[The effect of etiopathogenetic therapy of COVID-19 on the severity of the disease: results of a multicenter double-blind placebo-controlled randomized trial].

AIM: The search for etiopathogenetic agents to prevent the development of severe and extremely severe COVID-19 remains relevant. A placebo-controlled randomized clinical trial was conducted to evaluate the efficacy and safety of the antibody-based biological drug (Raphamin). MATERIALS AND METHODS: 785 outpatients 18-75 y.o. with laboratory confirmed mild COVID-19 were included within 24 hours from the disease onset. 771 patients were randomized to the group Raphamin (n=382) and the Placebo group (n=389). The study drug/placebo was prescribed for 5 days. The rate of progression to a more severe degree of COVID-19 by day 28 as well as the time to sustained clinical recovery and the frequency of hospitalization were evaluated. Safety was assessed taking into account adverse events, vital signs and laboratory parameters. RESULTS: The number of cases of progression to a more severe degree of COVID-19 in participants receiving Raphamin was 59 (15.5%) [52 (14.6%)] versus placebo - 89 (22.9%) [85 (23.7%)], ITT and [PP] analysis data are presented. The odds ratio between groups was OR=0.6157 [OR=0.5494], 95% confidence interval 0.4276-0.8866 [0.3750-0.8048], which meant a reduction in the chance of progression to a more severe degree by 38.4% [45.1%] or 1.48 [1.62] times; p=0.0088 [p=0.0019]. The time to sustained recovery in the Raphamin group was 4.5±2.4 [4.6±2.4] days, versus placebo - 5.8±4.7 [6.0±4.8] days; p=0.0025 [p=0.0036]. No adverse events with a certain relationship were registered. CONCLUSION: Raphamin reduces the risk of progression to a more severe degree of the COVID-19 and significantly shortens the duration of clinical symptoms.

Effects of Bone Marrow Multipotent Mesenchymal Stromal Cells and Their Secretion Products on the Cellular Composition of the Thymus and Spleen of Female Wistar Rats with Experimental Chronic Inflammation of the Internal Genitals.

The effects of bone marrow multipotent mesenchymal stromal cells and their secretion products on the subpopulation composition of thymic and splenic lymphocytes were studied in female Wistar rats with experimental chronic inflammatory process in the internal genitals. Stromal cells and medium conditioned by these cells in different administration routes (intravenous or lymphotropic injection) produces different modulating effect on blood leukocyte count and on subpopulation composition of the splenic and thymic lymphocytes. The most manifest anti-inflammatory effect was observed after lymphotropic injection of multipotent mesenchymal stromal cells creating a high concentration and long persistence of the factors produced by these cells in the focus of inflammation.

Cell Composition of Central and Peripheral Lymphoid Organs of Wistar Rats Treated with a Biomedical Cell Product.

We studied the effect of a biomedical cell product (bone marrow multipotent mesenchymal stromal cells and products secreted by these cells in conditioned medium) on subpopulation composition of lymphoid cells of central and peripheral lymphoid organs of Wistar rats under normal conditions. Changes in the subpopulation composition of lymphoid organs depended on the route of administration of biomedical cell product.

Chronodependent effect of interleukin-2 on mouse spleen cells in the model of cyclophosphamide immunosuppression.

We studied the chronodependent effect of IL-2 in the experimental model of immunodeficiency, cyclophosphamide-induced immunosuppression in mice. IL-2 in a dose of 100 U/ mouse was administered at 10.00 and 16.00 for 3 days after injection of cyclophosphamide. In contrast to the morning treatment with the cytokine, evening administration produced antiapoptotic effect on splenocytes and stimulated proliferation to a greater extent. This was accompanied by an increase in the number of CD4(+), CD25(+) and CD4(+)25(+) cells in the spleen to a level of intact mice. More pronounced effect of the evening mode of IL-2 administration on the proliferation and subpopulation composition of mouse spleen cells in the studied model can be associated with high blood level of CD25(+) cells at this time of the day.

Effect of Diprotin A, an Inhibitor of Dipeptidyl Peptidase IV, on Immunological Parameters of Lymphocytes in Intact Animals and Animals with Experimental Autoimmune Process.

We found the peculiarities of the effects of dipeptidyl peptidase IV inhibitor diprotin A on immunological parameters of lymphocytes in lymphoid organs in intact animals and in animals with experimental autoimmune process. In intact animals, diprotin A increased cellularity of the thymus and spleen, number of CD4+, CD8+, and CD4+8+ thymocytes and CD3+ splenocytes and reduced cellularity of lymph nodes and the number of antibody-forming cells in the spleen. Diprotin A administered against the background of autoimmune process, reduced thymus cellularity, number of antibody-forming cells in the spleen, and number of CD4 and CD4+8+ thymocytes in comparison with the corresponding parameters of autoimmune process.

Chrono- and Immunocorrection of Inflammatory Disorders of Internal Reproductive Organs in Women of Reproductive Age.

We compared the effectiveness of immunomodulators used in the treatment of patients with chronic salpingitis and oophoritis with or without changes in succinate dehydrogenase (SDH) activity in blood lymphocytes at incubation with the drug. Diurnal variations in individual reaction of SDH in blood lymphocytes to thymalin or ridostin were revealed. In the groups of women receiving ridostin or thymalin during the reaction of lymphocyte SDH to it, improvement of clinical laboratory and immunological parameters was observed in the majority of the patients and no effect was found in a lesser group of patients than in the groups treated with drugs during the absence of lymphocyte SDH reaction thereto. The timing of the presence of SDH reaction to drugs in the immunocompetent cells makes it possible to set the optimal daily regime of their application and to select a drug that would be most effective in each particular case.

Cellular Composition of the Spleen and Changes in Splenic Lysosomes in the Dynamics of Dyslipidemia in Mice Caused by Repeated Administration of Poloxamer 407.

We studied the effect of dyslipidemia induced by poloxamer 407 (300 mg/kg twice a week for 30 days) on cellular composition of the spleen and splenocyte lysosomes in mice. Changes in blood lipid profile included elevated concentrations of total cholesterol, aterogenic LDL, and triglycerides most pronounced in 24 h after the last poloxamer 407 injection; gradual normalization of lipid profile was observed in 4 days (except triglycerides) and 10 days. The most pronounced changes in the spleen (increase in organ weight and number of cells, inhibition in apoptosis, and reduced accumulation of vital dye acridine orange in lysosomes) were detected on day 4; on day 10, the indices returned to normal. Cathepsin D activity in the spleen also increased at these terms. The relationship between changes in the cellular composition of the spleen and dynamics of serum lipid profile in mice in dyslipidemia caused by repeated administrations of relatively low doses of poloxamer 407 is discussed.

Effects of Melatonin on Morphological and Functional Parameters of the Pineal Gland and Organs of Immune System in Rats During Natural Light Cycle and Constant Illumination.

We studied the response of the pineal gland and organs of the immune system to melatonin treatment in Wistar rats kept under conditions of abnormal illumination regimen. The animals were kept under natural light regimen or continuous illumination for 14 days and then received daily injections of melatonin (once a day in the evening) for 7 days. Administration of melatonin to rats kept at natural light cycle was followed by a decrease in percent ratio of CD4+8+ splenocytes and CD4-8+ thymocytes. In 24-h light with the following melatonin injections were accompanied by an increase in percent rate and absolute amount of CD4+8+ cells in the spleen, and a decrease in percent rate of CD11b/c and CD4-8+ splenocytes. In the thymus amount of CD4-8+ cells increased, and absolute number of CD4+25+ cells reduced. Melatonin significantly decreased lipofuscin concentration in the pineal gland during continuous light. Direction and intensity of effects of melatonin on parameters of cell immunity and state of the pineal gland were different under normal and continuous light conditions. It should be taken into account during using of this hormone for correction of immune and endocrine impairments developing during change in light/dark rhythm.

Effects of dipeptidyl peptidase IV inhibitor sitagliptin on immunological parameters of lymphocytes in intact animals and animals with experimental autoimmune process.

The effects of dipeptidyl peptidase IV inhibitor sitagliptin on immunological parameters were studied in animals with experimental autoimmune process. The effects of the drug administered in preventive (before manifestation of autoimmune processes) and therapeutic (after manifestation of autoimmune process) modes were studied.

Neuroprotective effects of erythropoietin in focal brain ischemia in rats.

Neuroprotective effect of erythropoietin administered before ischemia has been previously demonstrated. The efficiency of erythropoietin administration after ischemia was not studied, though in case of success these protocols would be applied in clinical neurology. In our experiments on the model of transitory focal ischemia, erythropoietin was injected intraperitoneally during the early and delayed postischemic period (3 and 12 h). The size of the necrotic zone, neurological deficit, and the severity of brain edema were evaluated in 48 h. Injection of erythropoietin in 3 and 12 h after ischemia significantly reduced the size of necrosis (p = 0.0007 and p=0.0016, respectively), neurological deficit (p=0.0013 and p=0.0062, respectively), and brain edema (p=0.02 and p=0.0186, respectively). Injection of erythropoietin after transitory focal cerebral ischemia produced a pronounced neuroprotective effect.

Effect of melatonin on cellular composition of the spleen and parameters of lipid metabolism in rats with alimentary obesity.

We studied the effects of melatonin on the status of immune organs and parameters of lipid metabolism in rats with alimentary obesity and parameters of lipid metabolism and immune status in Wistar rats kept on high-fat diet and receiving melatonin solution per os. Melatonin leveled the changes in blood and liver parameters of lipid metabolism, which was paralleled by normalization of cellular composition of immune organs. We conclude that melatonin can be a promising agent for the treatment of lipid metabolism and immune status disorders in alimentary obesity.

[Interrelations of pineal gland morpho-functional indices and immune system organs in rats exposed to natural illumination regime and continuous illumination].

The objective of this investigation was to determine the complex response of the pineal gland (PG) and of the organs of the immune system in Wistar rats in response to a violation of the illumination regime in the experiment. Animals were kept under natural light regime and continuous illumination for 14 days. After that rats were sacrificed and the mass of the body, PG, gonads, thymus and spleen was measured. Thymus and spleen cell subpopulations were determined by flow cytometry. The lipofuscin content in PG was determined by measuring an autofluorescence intensity in frozen tissue sections in the wavelength range of 505-545 nm using a confocal laser scanning microscope LSM 510 META (Carl Zeiss). The correlation analysis showed an increase in the amount and the change of sign and direction of relations between the indices of the state of PG and the immune system. This indicates the up-regulation of the intensity of inter-system relationships and the change of migration and differentiation vector of immunocompetent cells.

Activation of cathepsins B and L in mouse lymphosarcoma tissue under the effect of cyclophosphamide is associated with apoptosis induction and infiltration by mononuclear phagocytes.

We analyzed activities of lysosomal cystein cathepsins B and L in mouse LS lymphosarcoma and its drug-resistant RLS 40 strain and their correlations with the dynamics of the percentage of cells with fragmented DNA and CD14 (+) phagocytes over 3 days after cyclophosphamide injection. LS regression and inhibition of RLS 40 growth after cyclophosphamide injection were paralleled by an increase in cathepsins B and L activities in tumor tissues. The antitumor effect of cyclophosphamide associated with apoptosis intensity and protease activities were significantly higher in LS. Positive correlations between activities of cathepsins B and L and the LS tissue content of cells with fragmented DNA and CD14 (+) phagocytes and negative correlations thereof with tumor weight were detected. It seems that the increase in cathepsins B and L activities in LS tissues was caused by cyclophosphamide induction of apoptosis and depended on the level of tumor cell infiltration with mononuclear phagocytes.

Effects of thyroxin and mercazolyl on immunological parameters of blood lymphocytes and lymphoid organs.

Changes in the cellular and humoral immunity parameters were revealed in animals receiving thyroxin and mercazolyl per os for 2 weeks. Specific features of effects of the hormone and its inhibitor on the parameters of immune system were found.

Bezafibrate causes depression of the immune response and increases the sensitivity to endotoxin in association with low level of HDL and PPARα activity in hypertensive ISIAH rats.

We studied the effect of bezafibrate on hepatic PPARα activity and immune parameters in hypertensive ISIAH rats in comparison with normotensive WAG rats under conditions of LPS treatment. Bezafibrate increased activity of PPARα in WAG rats, but not in ISIAH rats. As differentiated from WAG rats, bezafibrate produced a potent effect on the content of T cell subpopulations in the thymus and spleen of ISIAH rats. Administration of LPS after injection of bezafibrate caused death of 50% ISIAH animals (but not WAG rats), which was associated with low level of HDL cholesterol and increased triglyceride content. Our results suggest that the hypolipidemic treatment (e.g., bezafibrate) can increase the severity of complications in patients with infectious and inflammatory diseases in association with low level of HDL.

Proliferative activity and subpopulation pattern of cells in murine thymus and spleen on the model of graft-versus-host chronic reaction under various diurnal regimens of IL-2 administration.

We studied the effects of IL-2 administration at different times of day to female B6D2F1 mice with experimental immunopathology, graft-versus-host chronic reaction induced by the administration of lymphoid cells from parental female DBA/2 mice. Recombinant murine IL-2 was injected subcutaneously at 10.00 (group 1) or 16.00 (group 2) after the first cell transfer. Evening administration of IL-2 in contrast to its morning injection prevented cell proliferation in the thymus and spleen, decreased the number of apoptotic splenocytes, significantly stimulated differentiation processes in the thymus, increased the amount of CD4 (+) 25 (high) thymocytes, and decreased the number of CD4 (+) 27 (low) splenocytes. These findings can serve as a prerequisite for the development of chronotherapeutic schemes for immunocorrection.

Blood microvesicles during chronic lymphoproliferative diseases.

The levels of CD19 (+) and CD20(+) microvesicles were estimated in the blood of patients with B-cell chronic lymphocytic leukemia and indolent non-Hodgkin lymphoma by flow cytometry method. It was found that the number of B cell microvesicles is several times higher in patients than in volunteers. The level of CD20 (+) microvesicles directly correlated with the number of CD20(+) lymphocytes in patients with chronic lymphoproliferative diseases. Extramedullary tumors cells can be a source of CD19 (+) microvesicles.

[The application of external and internal control objects in case of using of polymerase chain reaction and reverse transcription of polymerase chain reaction].

The external and internal control samples are used in case of polymerase chain reaction application to ensure validity of results. The external control samples are used to establish operability of reagents included into diagnostic kit. The internal control samples make it possible to check not only all the stages of reaction but also the process of amplification in each individual test tube with reaction mixture.

Viability of postmortal epididymal mouse spermatozoa during long-term hypothermic storage and cryopreservation.

The study examined the effect of long-term hypothermic (4°C) storage of mouse carcasses on motility, cell membrane damage, in vitro survival and capacitation of epididymal spermatozoa before and after cryopreservation. It was shown that the number of spermatozoa with rectilinear forward motion decreased with increasing storage time. There were no significant changes in the total sperm motility and integrity of their plasmalemma. Pronounced effects of hypothermia and long-term storage of the mouse carcasses on cryocapacitation of spermatozoa during cryoconservation were demonstrated.

[Effect of bioactive herbal preparations on structure of the gastric mucosa during stomach ulcer developing].

The present study was designed to determine experimentally the effect of a biologically active phytocomposition (BAP) on the gastric mucosa structural components during the formation and healing of ulcer induced by a single intraperitoneal injection of epinephrine. Experiments were conducted using 160 Wistar albino male rats. The fundic mucosa was studied 2, 5 and 10 days after the beginning of the experiment. The integrative assessment of a gastric mucosa was given by means of a statistical matrix method under the condition of phytocorrection. BAP was shown to change the rates of cell renewal that resulted in the restoration of the dimensions of mucosal compartments. Administration of BAP decreased the degree of mucosal damage and increased the initial size of mucosal compartments by 14-15%, as compared to those at similar time intervals in animals receiving no BAP. The number of neck mucous cells in the fundic glands was stably increased. Administration of BAP provided high parameters of the general normalization index for an organ. These changes collectively favored faster restoration of the gastric mucosa integrity after an ulcer. BAP was shown to have a protective and stimulating effect on the organ structures.