Features of the subpopulation composition of circulating NK and NKT cells in patients with subclinical atherosclerosis of lower limb arteries

Aim of the study was to investigate the features of the subpopulation composition of circulating NK and NKT cells and their diagnostic value in middle-aged patients, depending on the presence of subclinical atherosclerosis of lower limb arteries. Material and methods. The study included 80 patients (44 men (55.0 %) and 36 women (45.0 %)), whose age was 49.0 (44.0; 56.0) years. All patients underwent duplex ultrasound scanning (DUS) of the arteries of the lower extremities. Lymphocyte immunophenotyping was performed on a Navios 6/2 flow cytometer (Beckman Coulter, USA) using labeled mouse monoclonal antibodies CD45-PC7.0, CD16-PE, CD11b-FITC, CD4-APC, CD8-PC5.5, CD3-ECD manufactured by Beckman Coulter, USA. Results. According to the results of the DUS of the arteries of the lower extremities, the patients were divided into two groups: the first group included 46 (57.5 %) patients with lower extremity artery atherosclerosis, the second group included 34 (42.5 %) patients without plaques in lower extremity artery. Patients of first group had significantly higher, than patients of second group, number of circulating NK cells and lower number of CD4+CD11b+ NK cells. The decrease in the CD4+CD11b+ NK cell number ≤16.5 cells/μl allowed to diagnose lower extremity artery atherosclerosis with a sensitivity of 80.0 % and a specificity of 58.8 %. According to logistic regression analysis, a decrease in the number of CD4+CD11b+ NK cells ≤16.5 cells/μl was associated with a odds ratio of lower extremity artery atherosclerosis 5.71 (95 % confidence interval (CI) 1.44-22.6; p = 0.013). Conclusion. Compared with the control group, patients with lower extremity artery atherosclerosis differed in a statistically significantly larger number of circulating NK cells and a smaller number of CD4+CD11b+ NK cells. The decrease in the number of latter ≤16.5 cells/μl allowed to diagnose lower extremity artery atherosclerosis with a sensitivity of 80.0% and a specificity of 58.8 %.