Pathological Study on the Marginal Zone of the Spleen. Behavior of Marginal Zone to the Intravenously Injected Materials

Marginal zone of normal mice and treated mice with intravenous injection of four materials were studied on light microscopy. 1) The marginal zone of normal mice was shown as pale band between white pulp and red pulp. In the marginal zone, there were many cells which seemed to be corresponded to medium-sized lymphocytes. There ware small lymphocytes and reticulum cells in a moderate number in the marginal zone, while only a few macrophages were interspersed. Histochemically, acid phosphatese- and non-specific esterase-were arranged in a ring at the periphery of the white pulp, while a few metalophils were seen in the marginal zone. In alkaline phoshatase reaction, the cells, of which enzyme activity was lesser than that of endothelial cells, were moderately detected in the marginal zone. 2) Carbon, polystyrene latex, saccharated iron oxide and houseradish peroxidase (HrP) were intravenously injected into normal mice. In addition, HrP was intravenously injected the mice immunized with HrP. According to the finding that larger particles tended to stay longer in the marginal zone, the author suspected that the size of injected particles played an important role on the stagnation in the marginal zone.