Production of IL-2 and IFNγ by blood cells on exposure of different stimulators in vitro in children with chronic viral hepatitis c

Abstract

Significant progress has been made in the diagnosis and treatment of chronic viral hepatitis C (CHC). However, some aspects of the pathogenesis of CHC, such as the influence of various cytokines on the course of the disease and the effectiveness of therapy, require detailed research. Cytokine synthesis is a universal response of immunocompetent cells to any internal or external stimulation. Cytokine production by immunocompetent cells in response to various types of stimulation in infectious diseases is a topic of interest. In this regard, the aim of this study was to investigate IL-2 and IFNγ production by peripheral blood leukocytes of patients with chronic hepatitis C under the influence of various stimulators in vitro. Children aged 6 to 17 years were examined: 22 children with chronic viral hepatitis C; 29 conditionally healthy children. Blood was collected into vacuum tubes with heparin as an anticoagulant. Heparinized blood samples were diluted with glutamine-containing RPMI-1640 medium, and a series of 4 samples was prepared: a control sample without a stimulator; a sample stimulated with phytohemagglutinin; a sample stimulated with agonistic antibodies to CD3; a sample stimulated with agonistic antibodies to CD3 and agonistic antibodies to CD28. Blood samples were incubated for 24 hours (37 °C, 5% CO2). After centrifugation, supernatants were collected using an automatic dispenser, subjected to a single freeze, and stored at -20 °C until the time of the study. The concentration of IL-2 and IFNγ in whole blood cell cultures was determined by ELISA. The significance of differences between groups was assessed using the nonparametric Mann–Whitney test. It was found that in healthy children and patients with CHC, spontaneous production of IL-2 and IFNγ by blood cells was at the level of zero. The effect of various stimulators in vitro led to a significant increase in cytokine synthesis and allowed the investigation of the features of the cytokine profile in patients with viral hepatitis C. The concentration of IL-2 in the studied groups did not differ, regardless of the incubation option. The lower intensity of IFNγ synthesis in CHC compared to healthy children, in response to isolated and combined stimulation through the T cell receptor, indicates a decrease in the reserve capacity of producer cells in the context of chronic infection. The use of stimulators with different directions is a promising approach for studying immunoreactivity in the pathology of infectious and non-infectious origin.