Regulatory Influence of Blood Monocytes on the Population Composition of Granulocytes and the State of Their Respiratory Burst in the Widespread Purulent Peritonitis

Abstract

The aim of the study was to investigate the regulatory effect of monocytes and their subpopulations on the population composition of granulocyte leukocytes and the state of their respiratory burst in widespread purulent peritonitis (WPP). The study involved 24 patients aged 30-65 with acute surgical diseases and injuries of abdominal organs complicated by WPP. As a control 25 relatively healthy people of the same age range were examined. A study of the population composition of monocytes and granulocyte leukocytes in blood was performed using a two-platform technology on the hematological analyzer Sysmex XE-5000 (Sysmex Inc., USA) and FC-500 flow cytometer (Beckman Coulter, USA) using the Cytodiff antibody kit (Beckman Coulter, USA). A study of the monocytes number expressing HLA-DR- and CD64-receptor was performed by flow cytometry using direct immunofluorescence of whole peripheral blood. The respiratory burst state of neutrophilic granulocytes was studied by chemiluminescence analysis on a 36-channel chemiluminescence analyzer BLM-3607 (MedBioTech, Russia). As indicators of chemiluminescence were used luminol and lucigenin. The enhancement of chemiluminescence induced by zymosan was evaluated by the ratio of the area of the induced chemiluminescence to the spontaneous area and was defined as the activation index. It has been established that the immune-inflammatory process in WPP is characterized by a decrease in the number of classical monocytes in the peripheral blood and an increase in the content of non-classical monocytes. In WPP in peripheral blood the level of monocytes expressing HLA-DR receptors decreases. The change in the ratio of monocytes subpopulations characterizes the increase in the role of the proinflammatory fraction in the WPP pathogenesis. Changes in the population composition of granulocytes in the blood in patients with WPP also characterize the development of an acute inflammatory process. In this case, there is a decrease in the number of basophils in the peripheral blood, which, apparently, is determined by the presence of an allergic component in WPP and, accordingly, their migration to the inflammation area. In patients with WPP activation of a respiratory burst of granulocytes of blood was detected, the intensity of which is determined by the synthesis of primary and secondary active oxygen species. The results of the correlation analysis made it possible to establish that in WPP the regulatory role of non-classical monocytes increases aimed at stimulating the inflammatory processes (an increase in the number of mature and immature forms of neutrophils and stimulation of the activity of a respiratory explosion of granulocytes). The revealed features of the regulatory effect of monocytes on the population composition and the intensity of the respiratory burst of granulocytes can be used in the development of immunotherapeutic methods aimed at reducing the activity of the inflammatory process in WPP.