Lymphocytes play a role in the development of adipose tissue inflammation. Epicardial adipose tissue was shown to be a potential source of inflammatory mediators contributing to coronary atherosclerosis. The aim of the study was to assess lymphocyte content in peripheral blood, subcutaneous (SAT) and epicardial adipose tissue (EAT) in subjects with coronary artery disease (CAD) along with the effects of elective cardiac surgery. Twelve subjects without CAD (non-CAD group) and 24 age-, BMI- and HbA1C-matched subjects with CAD were included into the study. Blood, SAT and EAT samples were obtained before and at the end of elective cardiac surgery. Lymphocyte populations were quantified as percent of CD45+ cells using flow cytometry. Subjects with CAD had higher total lymphocyte (CD45+) amount in EAT compared to SAT (32.24±7.45 vs. 11.22±1.34%, p=0.025) with a similar trend observed in non-CAD subjects (29.68±7.61 vs. 10.13±2.01%, p=0.067). CD3+ cells were increased and CD3- cells decreased in EAT of CAD relative to non-CAD group with no difference between EAT and SAT. In both groups EAT showed reduced percentage of NK cells (CD15/56+CD3-) and elevated B cells (CD19+) relative to SAT (NK cells: 5.96±1.32 vs. 13.22±2.10%, p=0.012 for CAD and 5.32±1.97 vs. 13.81±2.72%, p=0.022 for non-CAD; B cells: 5.22±2.43 vs. 0.96±0.21%, p=0.039 for CAD and 12.49±5.83 vs. 1.16±0.19%, p=0.016 for non-CAD). CD8+ and NKT (CD16/56+CD3+) cells in EAT correlated positively with fasting glucose and HbA1C, while showing no association in SAT. Cardiac surgery decreased total lymphocytes in peripheral blood, SAT and EAT of both groups, while having only minor effects on lymphocyte subpopulations. To conclude, epicardial adipose tissue in subjects with CAD shows increased amount of total and CD3+ lymphocytes as compared with SAT or non-CAD subjects. These changes could contribute to the development of local inflammation and coronary atherosclerosis.
M. Mraz: None. A. Cinkajzlova: None. Z. Lacinov : None. J. Klouckova: None. H. Kratochvilova: None. M. Lips: None. P. Kopecky: None. M. Porizka: None. J. Lindner: None. M. Haluzik: None.