Invasive Species Compendium

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Abstract Full Text

Morphological features of age-related involution of the Thymus during parasitic invasion by Opisthorchis felineus (Rivolta, 1884).


Thymus (thymic, thymus gland) provides antigen-independent differentiation of lymphocytes, providing processes of cellular and humoral immunity in peripheral immune organs. After the onset of puberty, age-related involution of the organ occurs. Changes of thymus in parasitic invasions are found in the literature only for some types of pathogens, mainly of cestodosis group. No data on the influence of trematodes including Opisthorchis felineus (Rivolta, 1884) on thymus and its involution were found. Morphological study of the thymus was conducted at the invasion of Opisthorchis felineus (Rivolta, 1884) 1 month after infestation, in an invasive dose of 50 metacercariae. Microslides were studied by light and immersion microscopy, descriptive and comparative morphology. The design of the experiment divided the animals into two groups: the observation group consisted of invaded animals (Oryctolagus cuniculus) (n=10) and the control group (n=10). The results obtained were characterized by pronounced morphological signs of age involutionin Opisthorchis felineus (Rivolta, 1884) infestation, compared to the control, including a decrease in the volume of the medulla, replacement of the fatty tissue by lobules, an increase in the number of Hassall's corpuscle. These changes characterize earlier aging of the organ in case of parasitic disease.