In Covid-19, specific morphological changes in immune organs are accompanied by varying degrees of morphological changes depending on the nature of the pathogen and the general reactivity of the body. In any disease of the same viral nature, different subpopulations of T-lymphocytes (CD 3+,4+,carrying antigen) or B-lymphocytes (CD 20+, 23+) on the part of immune cells of varying degrees, a change in antigen-bearing populations, manifested by quantitative and qualitative changes. Changes in the immune organs are characterized by the accumulation of lymphocytes at different levels or the transition with metaplastic changes in parenchymal elements.

spleen, thymus, lymphocytes, lymphoid follicle, immune organs, immunohistochemistry.

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