Effect of low-intensity radiation on the morphological features of Peyer's plaque

Radiation has a negative impact on human health because of its high penetrating power. Mitoti-cally dividing cells and the lymphoid tissue of the gastrointestinal tract are most radiosensitive. The intestine is the major zone of sensitization and recycling of immunocytes that populate the mucous membranes of other organs. Immune-competent tissues of the digestive tract are repre-sented by lymphoid tissue, where the leading role belongs to Peyer's plaques-group accumula-tions of lymphoid tissue. The antigen-sensitized lymphocytes of Peyer's plaques migrate to the mesenteric lymph nodes, and from there through the lymphatic vessels through the thoracic duct and circulatory system and are directed to their own layer of the intestinal mucosa, mainly as IgA-secreting cells. This mechanism ensures the formation of clones of lymphocytes and the for-mation of specific antibodies in the areas of the mucous membrane that are remote from the fo-cus of primary sensitization. The important thing is that, unlike other lymphoid tissues that require infection or local immunization to form a germinal center, reproduction centers are always pre-sent in Peyer's plaques, regardless of the presence of infection.