Abstract
A correlative light and electron microscopic study is reported of pyknotic, phagocytized plasma cells in the mouse spleen following a single intravenous injection of sheep erythrocytes or rat bone marrow. Phagocytized plasma cells were observed in both red and white pulp between 3 and 7 days after antigen injection. A few mature plasma cells and plasma cells with Russel bodies were found 10 days after stimulation with no evidence of recognizable phagocytized plasma cells. Phagocytosis clearly plays some role in the removal of plasma cells from the spleen under the conditions employed in this study, although the possibility that significant numbers of plasmacytes migrate out of the spleen is considered. A correlation of phagocytized plasma cells with the log phase of antibody appearance in the circulation is indicated.