The Effects of Metallic Tin on Background Plaque-Forming Cells, Immunoglobulins and the Immune Response

Abstract

Inoculation of metallic tin powder into Lewis rats resulted in marked enlargement of the draining lymph nodes. Plasma cells were the major contributors to the increase in cell mass. Certain immunologic aspects of this plasma cell lymphadenopathy were investigated. Immunoglobulin isotypes were distinguished and quantitated by fluorescence immunocytochemistry and rocket electrophoresis of lymph node extracts. Background plaque-forming cells directed against sheep red blood cells were increased. Specific activity was highest 4 days after inoculation of tin. Lymph nodes and spleen continued to increase in cell number so that total background activity attained a maximum at 14 days after inoculation of tin. Tin was a good adjuvant for plaque-forming cells in lymph nodes and for serum agglutinins (primary and secondary responses) when the rats were immunized with sheep red blood cells, even when the antigen was injected at a remote site. The plasma cell response to tin may be due to local polyclonal activation.