Gender-specific Patterns of Immunoregulatory Cell Distribution in the Blood and Thymus: Association with Coronary Atherosclerosis and Vascular Aging

The aim of this study was to investigate the counts of immunoregulatory cells localized in the peripheral blood and thymus tissue of patients with chronic coronary artery disease (CAD) depending on gender.

Materials and methods. A cross-sectional, single-center comparative study was conducted, including 47 men and 16 women with chronic CAD. The severity of coronary atherosclerosis was assessed by calculating the Gensini score based on selective coronary angiography data. The vascular age index (VAI) was also calculated. The counts of FoxP3+ T regulatory lymphocytes (Treg) and T helper lymphocytes types 1 and 17 (Th1, Th17) in thymus obtained during coronary artery bypass grafting and in peripheral blood were assessed by flow cytometry.

Results. Women had higher absolute counts of terminally differentiated Tregs (CD25^loFoxP3+ Tregs) in the blood and showed a trend toward an increased proportion of Tregs in the total CD4+ cell population in the thymus compared to men. Only in women was the number of Tregs in the blood correlated with both the Gensini score and the VAI.

Conclusion. Thus, the distribution of Tregs in the blood and thymus in CAD has gender-specific characteristics: women have signs of prior Treg activation, which may contribute to limited severity of coronary atherosclerosis compared to men.

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