The light and the electron microscopic studies of Peyer's patches in non germ‐free adult mice

Abstract

Peyer's patches of conventional adult mice are studied with light and electron microscopy. Based on cellular types and distribution, each lymphoid follicle of Peyer's patch is divisible into four zones: the germinal center, the small lymphocytic, the interfollicular and the subepithelial zones. Three distinct cell types are present in the germinal center, i.e., dendritic reticular cells; tingible body macrophages; and lymphocytes which are classifiable into large, medium and small size. The medium size lymphocytes are the great majority in this zone. The small lymphocytic zones are characterized by a predominance of small lymphocytes with a few reticular cells. The subepithelial zone has a remarkable accumulation of macrophages and plasma cells. In the interfollicular zones there are predominantly small lymphocytes with considerable round macrophages and plasma cells, and this zone is permeated with several post‐capillary venules. The distinctive characteristics of small capillaries of the patches are also described. Copyright © 1971 Wiley‐Liss, Inc.