Association of FoxP3<sup>+</sup> T regulatory lymphocytes with epicardial adipose tissue thickness in patients with coronary heart disease

Abstract

Background. Increase ofthe epicardial adipose tissue (EAT) thickness isassociated with development of inflammation and cardiovascular complications, however, there is no data on the relationship between EAT thickening and the number of immunosuppressive regulatory T lymphocytes.The aim. To study the number of circulating T regulatory lymphocytes and nuclear translocation ofthe FoxP3 transcription factor in patients with stable coronary heart disease (CHD) depending on the epicardial adipose tissue thickness.Materials and methods. We examined 30 patients with chronic stable CHD. The EAT thickness was measured by echocardiography. Patients were divided into groups depending on the presence and absence of EAT thickening above 5 mm (groups 1 and 2, respectively). Imaging flow cytometry was used to determine the number of T regulatory lymphocytes and the level of FoxP3 nuclear translocation. The concentration of cytokines and high sensitivity C-reactive protein (hsCRP) was determined using enzyme-linked immunosorbent assay in blood serum.Results. Anthropometric indicators of obesity and the severity of atherosclerosis were comparable between groups. In group 2, there was an increase in low-density lipoprotein cholesterol concentration (p = 0.043), ratio of low-density lipoprotein cholesterol tohigh-density lipoprotein cholesterol (p = 0.017) and the concentration ofhsCRP (p = 0.044) andIL-1β (p = 0.005), adecrease in the number and relative count of Tregulatory lymphocytes (p = 0.020 andp = 0.026, respectively), aswellas thenumber of cells withFoxP3 nuclear translocation (p = 0.018) compared togroup1. According tomultiple logistic regression, the concentration ofhsCRP, IL-1β and T regulatory lymphocytes relative count in total were the predictors of EAT thickening (accuracy 80 %; sensitivity 75 %; specificity 84,6 %; AUC = 0.89).Conclusions. Thickening of epicardial adipose tissue inpatients withcoronary heart disease is associated with a decrease in the number of T regulatory lymphocytes andFoxP3 nuclear translocation inthem in presence of comparable anthropometric parameters of obesity and the severity of coronary atherosclerosis.