CORRELATION BETWEEN THE NUMBER OF CD3+ AND CD4+ LYMPHOCYTES AND THE EXPRESSION LEVEL OF MONOCLONAL ANTIBODIES TO TYROGLOBULIN IN TTF-1 AND KІ-67 IN RAT'S THYROID GLAND UNDER PRENATAL ANTIGEN INFLUENCE

Abstract

Summary. Recently, the incidence of children and adolescents with thyroid pathology, especially of autoimmune origin, has been growing rapidly. The development of such conditions, according to the research, is facilitated by the immunological background, which is formed under the influence of antigens, including infectious genesis, both pre- and postnatally. Thus, the question arises as to how different classes of lymphocytes affect follicular thyrocytes under the conditions of prenatal action of thyroid-nonspecific antigen, the intensity of exposure and the vector of interaction.

The aim of the study – to determine the presence and intensity of interaction between immunohistochemically determined CD3⁺ and CD4⁺ lymphocytes and immunomorphological expression of thyroid-specific antibodies to thyroglobulin, TTF-1 and Ki-67 using Pearson's correlation coefficient.

Materials and Methods. The thyroid glands of Wistar rats at the age of 1 to 60 days after birth were studied (162 animals): Group I – intact animals (normal); Group II – control, animals were administered intrauterine 0.9 % NaCl solution; Group III – experimental animals injected with staphylococcal toxoid purified by adsorbed fluid (10–14 binding units in 1 ml, diluted 10 times) in utero on day 18 of pregnancy. Histological sections with a thickness of 4 μm were stained with hematoxylin and eosin, immunohistochemically using monoclonal antibodies CD3 (5B2), CD4 (5B4), Thyroglobulin Antibody (1D4) (Tg Ab) and TTF-1 (8G7-3 / Ki-), Ki-67) Santa Cruz Biotechnology, Inc. and Mayato hematoxylin staining. Morphometry was performed using a Carl Zeiss microscope "Primo Star" using an AxioCam camera, a set of morphometric studies was performed using the Zeiss Zen program (2017). The calculation of the Pearson correlation coefficient (r) was performed using Microsoft Office Excel 2010.

Results. The presence and intensity of interaction between immunohistochemically determined CD3-, CD4-, TTF-1- and Ki-67-positive cells, such as immunohistochemical expression of thyroglobulin, which change intensively in the period from 11 to 30 days after prenatal exposure to staphylococcal toxoid on organism and differ significantly from such indicators in the intact and control groups. Up to 60 days, the correlation coefficients for the above indicators do not differ significantly in all groups of experimental animals.

Conclusions. A correlation was found between CD4⁺ lymphocytes and TTF-1 positive cells. In intact animals, this relationship after birth is moderate and by the 60th day is almost unchanged. In experimental animals, in contrast to intact animals, the degree of communication increases until the 60th day. The relationship between TTF-1 + thyrocytes and the degree of expression of antibodies to thyroglobulin (r (TTF-1: TG)) in experimental animals is higher than in intact animals, and remains so until the 60th day of life. The degree of relationship between T lymphocytes and proliferating cells (r (CD3: Ki67)) after birth is greater in experimental animals, and gradually increases to 30 days. The degree of relationship between CD3⁺ lymphocytes and the degree of expression of antibodies to thyroglobulin (r (CD3: TG)) after birth is greater in intact animals, but gradually decreased, compared with experimental, which had a reverse trend. Thus, the quantitative and class composition of the T-lymphocyte pool of the thyroid gland affects the general and specialized proliferation and synthetic activity of thyrocytes, which in dynamics is an adaptive response to the prenatal action of staphylococcal toxoid.