The state of functional activity of neutrophils in patients with various variants of carbohydrate metabolism disorders who have had SARS-COV-2S infection

Abstract

According to the Federal State Statistics Service of the Russian Federation, there has been a significant increase in the prevalence of prediabetes and type 2 diabetes mellitus (DM). Type 2 diabetes is characterized by frequent disability due to the progression of complications of diabetes and high mortality. Domestic and foreign authors have shown that neutrophils play an important role in the development of diabetic micro- and macroangiopathies. It has been shown that in DM, changes in the functional activity of neutrophils are observed, manifested in a decrease in chemotactic activity, changes in phagocytic activity, leukotriene production, and secretion of lysosomal enzymes. According to the results of previous studies, ambiguous data were obtained on the effect of high hyperglycemia in DM on the phagocytic activity of neutrophils. Thus, foreign authors have shown that in DM, when the target levels of glycemic control are not reached, the phagocytic activity of neutrophils is inhibited. Other researchers have found that with DM, activation of the phagocytic function of neutrophils is detected, but at the same time, the reaction of neutrophils to additional stimulation with latex (according to the results of the HCT test), a decrease in the expression of adhesion molecules on their surface and the ability to form extracellular traps occurs. Neutrophils, being the main cells of innate immunity, play an important role in the antiviral response. Patients with impaired carbohydrate metabolism are at high risk of severe course and unfavorable outcome of SARS-CoV-2 infection. The course and outcome of an infectious disease depends on how the effector functions of neutrophils are realized. The aim of the study was to study the features of the functional activity of neutrophils in patients with various variants of carbohydrate metabolism disorders who had SARS-CoV-2 infection. The study included 20 patients with impaired carbohydrate metabolism who had suffered SARS-CoV-2 infection, the control group included 15 clinically healthy volunteers. In all groups, the phagocytic activity of latex particles with a diameter of 1.7 microns was evaluated by neutrophils (phagocytosis activity, phagocytosis intensity, phagocytic number); spontaneous and induced NBT activity of neutrophils by morphological method. A significant increase in the absorption capacity of peripheral blood neutrophils, an increase in the phagocytic activity of leukocytes in the group of patients with impaired carbohydrate metabolism was revealed. A simultaneous increase in the indicators of spontaneous and induced HCT tests was found in the group of patients with impaired glucose tolerance and in the group of patients with type 2 diabetes mellitus. The observed disorders in the phagocytic link are an important factor in reducing the overall immunoreactivity of patients, which determines the long rehabilitation period. Identifying the features of innate immunity in patients with various variants of carbohydrate metabolism disorders who have suffered from SARS-CoV-2 infection will further help develop an individual strategy for the prevention and treatment of these diseases.