An increase in activated NKT-CD8+ cells is associated with the presence of hypoechoic carotid plaques

Abstract

Abstract Background The role of NK-cells and NKT-cells and their subtypes at various stages of the development of atherosclerosis is poorly understood. It was previously shown that CD3+CD56+CD8+ cells can secrete pro-inflammatory cytokines and an increase in their number has been established in patients with active Behçet's Disease and Multiple Sclerosis. Purpose To study the relationship between the number of activated CD3+CD56+CD8+ cells and the echogenicity of plaques in patients with carotid atherosclerosis. Methods The study included 40 patients, 21 (52.5%) men and 19 (47.5%) women who underwent carotid ultrasound and immunological studies. The median age was 53.5 (46.7; 57.0) years. All patients underwent duplex ultrasound scanning of the carotid arteries. If an atherosclerotic plaque was detected, its image was saved and exported to Adobe Photoshop CS6® followed by analysis of the gray-scale median (GSM) of the plaque. Hypoechoic was considered a carotid plaque whose GSM values were less than 50. The number of CD3+CD56+CD8+CD11b+ cells was evaluated by flow cytometry using a flow cytometer. Results Among the examined patients, carotid plaques were detected in 31 (77.5%) participants. The average values of GSM visualized plaques were 58.0 (46.0; 71.5). Atherosclerotic plaques with GSM <50 were detected in 11 (35.5%) patients. In patients with hypoechoic carotid plaques, the number of CD3+CD56+CD8+CD11b+ cells was statistically significantly higher – 352 (55.0; 505) cells/uL versus 66.0 (15.5; 138) cells/uL in patients with plaques whose GSM values were more than 50 (p=0.020). Based on the results of correlation analysis it was established inverse relationship between number of CD3+CD56+CD8+CD11b+ cells and GSM of plaques (r=−0.427; p=0.016). According to the results of the ROC-analysis, an increase in the number of activated NKT-CD8+ cells over 46.5 cells/uL was a predictor of the presence of hypoechogenic carotid plaques with a sensitivity of 81.8% and a specificity of 45.0% (see Figure 1). Conclusion In patients with hypoechoic carotid plaques, the number of CD3+CD56+CD8+CD11b+ cells was significantly higher in comparison with other patients. An increase in the number of activated NKT-CD8+ cells over 46.5 cells/uL was a predictor of the presence of hypoechoic carotid plaques with sensitivity of 81.8% and specificity of 45.0% Figure 1 Funding Acknowledgement Type of funding source: None