[Lymphoid structures of human duodenum in adolescent and juvenile age]

Using morphometric methods, the microtopography and quantitative proportions of lymphoid cells in structural components of lymphoid tissue were studied in the duodenal wall of the persons of adolescent and juvenile age. In adolescence, in contrast to juvenile age, the intestinal wall was found to contain all the morphological structures, characteristic to functional activity of lymphoid tissue (lymph nodules with and without the germinal centers). In adolescence numerous cells in mitosis and immature cells were found in intestinal lymphoid structures, while no mitotic figures were detected in the similar structures in juvenile age. Duodenal lamina propria contained more antigen-producing plasma cells in adolescence than in youth. This complex of cell correlations is indicative of enhanced local immune response in adolescence and may be explained by an age-dependent active neuro-hormonal body reconstruction.