The severity of internal carotid artery stenosis is associated with the circulating Th17 level

Immune and inflammatory reactions contribute to the progression of atherosclerosis. The walls of the different arteries and segments of the arteries have heterogeneous haemodynamic and histological features. We aimed to explore the relationship between the circulating T-cell subsets and the abundance of carotid atherosclerosis in different segments of carotid arteries.

70 patients underwent ultrasound duplex scanning to determine the degree of stenosis of the common carotid artery (CCA), the CCA bifurcation or the internal carotid artery (ICA). The blood frequencies of T-, B-, NK-cells, regulatory T cells (Treg), activated T-helpers (Th), IL10-producing Th, Th1 and Th17, as well as blood levels of hsCRP, sCD25, IL10 and IL17a were assessed.

The frequencies of Th17 were increased in patients with ICA stenosis >35% and >50% vs. patients with ICA stenosis <35%. Th17 blood level ≥0.55 % of lymphocytes was associated with more severe stenosis of ICA (OR 4.3 (1.0-17.6), p < 0.05 for ICA stenosis of 35-50% and 6.8 (1.3-35.0), p < 0.05 for ICA stenosis >50%). BMI positively correlated with the CCA bifurcation stenosis degree (r = 0.33, p < 0.05).

The severity of ICA stenosis can be associated with the circulating Th17 level.