[Effector and regulatory blood lymphocyte subpopulations in stable coronary artery disease]

To investigate a balance between circulating regulatory T lymphocytes (Treg) exerting antiatherogenic activity and T helper type 1 (Th1) and T helper type 17 (Th1 7) cells having proatherogenic activity in patients with stable coronary artery disease (CAD) and different degrees of coronary atherosclerosis.

According to coronary angiography findings, 80 patients were allocated to 4 groups: 1) 18 patients with intact coronary arteries; 2) 21 with no progressive coronary atherosclerosis; 3) 16 with progressive coronary atherosclerosis (more than 50% stenosis) in the native coronary arteries; 4) 25 patients with three-vessel lesions. Groups 2 and 3 patients had undergone coronary stenting 23.8 ± 8.4 and 22.4 ± 8.7 months before their enrollment, respectively. Lymphocytes were typed by direct immunocytofluorometry: Treg was defined as CD4+CD25highCD127low and CD4+FoxP3+ lymphocytes. For CD4+IL-17a+ Th17 and CD4+INFgamma Th1 analysis, mononuclear cells were preactivated by culture. The serum levels of high-sensitivity C-reactive protein, IL-10, sCD25, and IL-17a were determined by nephelometry, chemiluminescence (Immulite) and ELISA, respectively.

Group 4 was found to have lower Treg levels and higher Th17 levels than Group 1. The ratio of Th17/Treg proved to be higher in Groups 3 and 4 than in Group 1 and that of (Th1+Th17)/Treg was higher in Group 3 than in Group 2. The female patients had higher Tregs levels than the male ones. The Th17/Treg index turned out to be increased in patients with a history of myocardial infarction.

The imbalance of pro- and anti-atherogenic lymphocyte subpopulations plays a role in the pathogenesis of CAD and is associated with progressive atherosclerosis.