STRUCTURAL CHANGES IN THE THYMUS UNDER THE PATHOGENIC FACTORS ACTION

Prykhodko O. O.

LITERATURE REVIEWS

Scentific article

The thymus is the primary lymphoid organ in which antigen-independent proliferation and differentiation of T-lymphocytes occurs. After that, T-lymphocytes enter the blood and populate secondary lymphoid organs. The aim of study was to analyze and generalize data from modern scientific literature regarding structural changes in the thymus under the conditions of exposure to various exo- and endoantigens. Having followed the patterns of structural reorganization of the thymus under the influence of certain pathogens, it is possible to predict its further changes, as well as to develop methods of their prevention and correction. In general, the structure of the rat thymus is typical and close to the structure of this gland in humans. Due to which this experimental model is justified and probable, the obtained data can be extrapolated to a person. This organ is involved in maintaining homeostasis and protecting the body from foreign antigens. With age, the tissue of the thymus undergoes involutional changes, which further worsens the condition of the body and complicates the course of chronic diseases. Age-related involution leads to a progressive decrease in the formation of new T cells. This reduced output is compensated by duplication of existing T cells, but this leads to a gradual dominance of memory T cells and a reduced ability to respond to new pathogens or vaccines. Atrophy of the organ is indicated by the deterioration of the thymus microenvironment, fibrosis and adipogenesis. Thymic function is critical for reducing morbidity and mortality associated with a variety of clinical conditions, including infections and transplantation. The thymus is necessary for the development and maturation of T cells. It is extremely sensitive to atrophy, in which there is loss of thymus cellularity and disruption of its architecture. This can lead to a decrease in the yield of naive T cells. Atrophy of the thymus is often associated with aging. Therefore, the study of changes in its structural components and vascular bed under the influence of various pathological factors is an important task of morphologists and clinicians. Under the conditions of shortterm influence of any factor on the body of experimental animals, all changes in the thymus are a manifestation of a compensatory-adaptive reaction and are not specific. Under the conditions of long-term exposure, a decrease in cell density, apoptosis of lymphocytes, loss of functional capabilities of the organ is observed.

thymus,experiment,cortical substance,brain substance,lymphocytes

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«Bulletin of problems biology and medicine» Issue 1 (168), 2023 year, 62-72 pages, index UDK 611.438+599.23 +616.438

10.29254/2077-4214-2023-1-168-62-72