[Structural and immunologic indicators of Peyer's patches in the human fetus].

Histological and immunological methods were used for the investigation of the development of Peyer's patches in the ileum of 110 human fetuses of 8-29 weeks of gestation. The formation of Peyer's patches and the increased number of lymphatic follicles in them are described. Beginning from 8th-9th week of gestation T- and B-lymphocytes and their subpopulations (auto-RFC, EAC-RFC, IgM- and IgG-positive cells) can be identified in mononuclear cell suspension obtained from Peyer's patches. An increase in their number during embryogenesis and the pathways of lymphocyte migration are shown. By the moment of birth "O" cells dominant in Peyer's patches and later on E-RFC and IGM-positive cells prevail. Auto-RFC are the most scanty. The authors regard Peyer's patches as peripheral organs of immunogenesis involved in local defensive reactions and in the fetal immunogenesis system on the whole.