Vol 20, No 1 (2023)

The pandemic of the new coronavirus infection COVID-19, caused by the SARS-CoV-2 virus, continues to be a serious problem for the entire global community. Currently, most patients experience mild COVID-19, with only about 20% of those infected requiring hospitalization. The severe course of COVID-19 is most often associated with damage to the patient’s bronchopulmonary system by the virus and serious abnormalities, including damage to the air-hematological barrier, systemic inflammation, dysfunction of the immune system and the addition of secondary infections. Severe disease and poor outcome in hospitalized patients with COVID-19 may be associated with lymphopenia in combination with neutrophilia. Restoring the number of lymphocytes is important to improve the prognosis of the patient’s outcome. Patients with COVID-19 experience an immune imbalance where systemic inflammation and dysfunction of circulating T and B cells lead to more severe disease. TREC/KREC analysis can characterize the function of the central organs of the immune system and its relationship with clinical and laboratory data. Decreased TREC/KREC levels were observed in patients with unfavorable disease outcomes compared to patients with favorable disease outcomes. Additionally, a higher neutrophil to lymphocyte ratio was found. Levels of TREC and KREC in the blood negatively correlate with the neutrophil-lymphocyte ratio. Thus, the TREC/KREC assay is a potential prognostic marker for assessing the severity and outcome of COVID-19.

Aim: to evaluate the secretory activity of mononuclear blood leukocytes by the level of in vitro production of oppositional cytokines (pro-inflammatory IL-6 and anti-inflammatory IL-10) in rats in a model of diet-induced metabolic syndrome (MS) against the background of changes in the concentration of adipokines leptin and adiponectin.

Materials and methods. In male Wistar rats, MS was modeled by keeping for 12 weeks on a high-fat and high-carbohydrate diet; control group animals received a normal diet. Mononuclear leukocytes isolated by gradient centrifugation from heparinized blood were cultured in a medium based on RPMI-1640 (concentration of 2×10⁶ cells in 1 ml of medium) for 24 hours in sterile tubes in a CO₂-incubator in two variants – without the addition of an inducer and with the addition of bacterial lipopolysaccharide (LPS). The concentration of cytokines in the culture fluid, hormones leptin and adiponectin in the blood serum was determined by enzyme immunoassay. Statistical data processing was carried out in the SPSS Statistics 23.

Results. In animals exposed to a 12-week high-fat and high-carbohydrate diet, against the background of an increase in body weight, the specific mass of visceral adipose tissue, metabolic disorders (hyperglycemia, impaired glucose tolerance, dyslipidemia), high concentrations of leptin and low concentrations of adiponectin, the ability of mononuclear blood leukocytes to produce IL-6 and IL-10 in vitro at the basal level and when stimulated by bacterial LPS does not change.

Conclusion. Probably, the morphofunctional status and secretory profile of monocyte-macrophage system cells depends on the severity and duration of the metabolic and hormonal imbalance associated with obesity and systemic chronic inflammation.

Aim: to evaluate the effect of a dry extract of the herb of Cichorium intybus L. on the production of cytokines by human peripheral mononuclear cells in the systems in vitro and on the mass (thymus, spleen) and number of cells (thymus, spleen, bone marrow) of immune organs of mice in a model experiment of immunodeficiency in the systems in vivo.

Materials and methods. The study of the immunoregulatory properties of the dry extract of chicory herb was evaluated by the ability to change the production of cytokines on the model of mononuclear cells during co-cultivation under in vitro conditions and by the ability to restore the mass (thymus, spleen) and the number of cells (thymus, spleen, bone marrow) of the organs of the immune system of outbred mice under conditions of immunosuppression induced by methotrexate to the level of intact mice in vivo.

Results. An analysis of the immunoregulatory properties of dry extract of chicory herb in the systems in vitro showed that a solution of chicory extract increased the concentration of the anti-inflammatory cytokine IL-10 and reduced the production of pro-inflammatory cytokines TNFα, IL-6, IFNγ and anti-inflammatory cytokine IL-1Ra. Evaluation of the effect of the dry extract of chicory herb in the systems in vivo found that the dry extract of the herb of Cichorium intybus L. had no effect on the mass (thymus, spleen) and number of cells (thymus, spleen, bone marrow) of the immune system organs in intact mice and restored these parameters of the immune system in animals treated with cytostatic MTX to the level of intact animals, and the effect of the extract was comparable to the effect of the reference drug “Immunal”.

Conclusion. The dry extract of the herb of Cichorium intybus L. can be considered as a promising agent that normalizes the parameters of the immune system under conditions of MTX-induced immunosuppression, suppresses the synthesis of pro-inflammatory cytokines and stimulates the secretion of anti-inflammatory IL-10, and the activity of this extract is associated with high content of phenolic compounds. Given the above, further study of chicory herb and dry extract from it is expedient and aimed at creating new effective herbal preparations that regulate the functions of the body’s immune system.

Hyperinflammation and dysfunction of the immune response during COVID-19 infection develops due to the reaction of innate immune cells to the introduction of the SARS-CoV-2 virus. The expression of receptors on these cells reflects the degree of their activation and makes it possible to assess the intensity of inflammation. The purpose of this study were to study the structural and functional features of innate immunity cells in patients. The specific gravity and absolute content of neutrophils (CD11b⁺, CD16⁺, CD18⁺) and monocytes (CD14⁺CD16^–, CD14^–CD16⁺, CD11b⁺, CD18⁺) in the peripheral blood of patients were determined. The contingent of the study included 60 people, of which: 47 had had a coronavirus infection COVID-19 (confirmed by PCR) in the 12 weeks preceding the study, and 13 had no history of it. In the peripheral blood of people who had COVID-19, compared with those who had not been ill, a significantly lower number of monocytes of the classical (CD14^–CD16⁺) and, on the contrary, a greater number of non-classical (CD14⁺CD16^–) cell populations were determined (p<0.05). Also in these individuals, a high proportion of monocytes carrying the adhesion receptors CD11b and CD18 (p<0.01) and a high content of neutrophils expressing the adhesion receptor CD11b⁺ and CD16⁺ (p<0.05) was noted. Thus, the results of a study of the expression of various types of receptors on monocytes and neutrophils illustrated the long-term preservation of aberrant structural and functional characteristics of innate immunity cells in individuals who underwent COVID-19.

Aim: Studying of the respiratory burst state and NAD(P)-dependent dehydrogenases activities in blood neutrophils features in the forecast of the development of abdominal sepsis in patients with widespread purulent peritonitis (WPP).

Materials and methods. The study involved 50 patients with WPP in the preoperative period. Abdominal sepsis was developed by 35 patients (70.0%) from 5 to 10 days postoperative period, 15 patients (30.0%) hadn’t complications. The respiratory burst condition of blood neutrophils was examined using a chemiluminescent assay. Intracellular activity of the NAD- and NADP-dependent dehydrogenases was researched with using bioluminescent methods.

Results. It was found that patients with WPP whose dynamics of the preoperative period will develop sepsis the chemiluminescent activity of blood neutrophils was characterized by a reduced level of spontaneous synthesis of the primary reactive oxygen species (ROS) and elevated levels of spontaneous synthesis of secondary ROS relative of the indicators identified in patients without subsequent complications. The feature of neutrophil metabolism in WPP patients without subsequent development of sepsis was high activity of the anaerobic lactate dehydrogenase reaction and decrease in activity of the NADP-dependent decarboxylating malate dehydrogenase. In patients with WPP and the subsequent development of sepsis was found high level of NAD-dependent substrates outflow citric acid cycle in the reaction of amino acid metabolism via glutamate dehydrogenase that may affect the activity of aerobic respiration in the neutrophils. Using correlation analysis was found that the intensity of the neutrophils respiratory burst in patients with no subsequent complications depends on the activity of anaerobic glycolysis.

Conclusion. The established differences in the state of the respiratory burst and the activity of enzymes in neutrophils in patients with WPP, in depending on the subsequent development of the sepsis, determine the possibility of developing the method of forecasting complications and developing immunoactive therapy in the postoperative period of WPP. 

The novel coronavirus infection (COVID-19) has a suppressive effect on innate immunity, which is a prerequisite for developing strategies to enhance this non-specific link as a preventive measure to protect against other respiratory infections during the ongoing circulation of mutating strains of the SARS-CoV-2 virus. Despite the currently developed and available preventive measures, it has been noted that in persons who have undergone COVID-19, repeated episodes of both coronavirus infection and diseases caused by other pathogens have been recorded.

This review analyzes data from the biomedical literature and considers examples of health risks associated with continued infection with pathogens that cause respiratory tract pathologies. It also reflects the ways and approaches of possible preventive measures, the purpose of which is to prevent the development of pathologies of both the respiratory organs and other systems.