SPLEEN FOCUS IN FRIEND'S DISEASE: HISTOLOGICAL STUDY

The spleen foci of Friend's disease in early stages, which appeared in male DDD mice 3-12 days after the inoculation of diluted virus solution, were histologically examined. The cells of the spleen foci were monotonously large and polygonal, histologically resembling young reticulum cells. They were consistent with the Friend tumor cells of the spleen in the advanced stage. Their first appearance was observed in the periphery of the arterioles in the red pulp, more frequently beneath the splenic capsule, which was followed by their extension to the splenic trabeculae. The earlier spleen foci were usually separate from the erythroblastic cell groups, but a few or several seemingly normal erythroblasts were infrequently found among them.