IMMUNOHISTOCHEMICAL FEATURES OF CD95 AND CD163 EXPRESSION IN THE THYROID GLAND UNDER COMBINED MICRONUTRIENT DEFICIENCY

Abstract

This experimental study investigated immunohistochemical changes in the thyroid gland under combined magnesium, iron, selenium, and zinc deficiency. Particular attention was paid to the expression of CD95 and CD163 as markers reflecting apoptosis-associated cellular responses and macrophage activity. In intact animals, CD95 and CD163 expression was low, accounting for 2.14% and 5.08%, respectively. Under combined micronutrient deficiency, CD95 expression increased to 7.13%, indicating enhanced susceptibility of follicular epithelial cells to apoptosis. The most pronounced changes were observed in CD163 expression, which increased to 48.3%, reflecting marked activation of macrophage-associated inflammatory and reparative processes. These immunohistochemical alterations were accompanied by structural remodeling of the thyroid tissue, including disorganization of the follicular apparatus, reduction in follicular size and epithelial height, decreased colloid content, and an increased stromal component. The findings indicate that combined Mg, Fe, Se, and Zn deficiency induces complex cellular and tissue responses in the thyroid gland involving both apoptosis-related mechanisms and macrophage-associated inflammatory and reparative processes. CD95 and CD163 may be considered informative immunohistochemical markers for assessing the severity of thyroid tissue remodeling under experimental micronutrient deficiency.