Features of interleukin-19 production in patients with atherosclerosis

Objective. To study the features of local and systemic production of interleukin-19 in patients with atherosclerosis.Material and Methods. The study comprised a total of 46 patients (26 women and 20 men) treated for arterial hypertension in the therapeutic department of Republican Clinical Hospital named after G.Y. Remishevskaya. The mean age of subjects was 63.4 ± 3.2 years. The control group included 40 patients (23 women and 17 men aged 44.7 ± 5.5 years) who did not have atherosclerosis. Samples of atherosclerotic plaques and venous blood were examined. Atherosclerotic plaques were obtained by endarterectomy and then subjected to homogenization followed by enzymatic hydrolysis for 1 h at 37 °C with collagenase IV in the presence of proteinase III inhibitors. The serum levels of cytokines (in the control group and in patients with atherosclerosis) and in the atherosclerotic plaque homogenate (in patients with atherosclerosis) were determined by ELISA. To assess the cytokine-producing capacity of blood leukocytes and white blood cells isolated from atherosclerotic plaques, spontaneous and phytohemagglutinin (PHA)-induced cytokine production was determined when the cells were cultured in RPMI-1640.Results. The serum levels of IL-19 did not significantly differ between the patients with atherosclerosis and the control group. A statistically significant two-fold increase in the spontaneous expression of IL-19 by blood leukocytes was observed in the group of patients with atherosclerosis in comparison with the control group. When comparing the contents of IL-19 in blood serum and atherosclerotic plaque homogenate in patients with atherosclerosis, no statistically significant differences were found (p = 0.182). The level of PHA-induced IL-19 production by the atherosclerotic plaque white blood cells was significantly lower than that of blood leucocytes.Conclusion. The study showed that the reserve capacity for IL-19 synthesis in the atherosclerotic plaque white blood cells decreases leading to the progression of inflammation. The obtained results suggest that IL-19 plays the anti-atherogenic role and its production is involved in the maintaining the mechanisms for down-regulation of inflammation in atherosclerotic plaques.