EXPERIMENTAL DELAYED TYPE ALLERGY WITHOUT DEMONSTRABLE ANTIBODIES .2. IN VITRO ACTIVITY OF RETICULO-ENDOTHELIAL CELLS

Abstract

In guinea pigs a delayed type allergy against sheep erythrocytes (SE) was obtained without the presence of cytophilic antibodies. The affinity for the antigen of the reticulo-endothelial cells of such animals was studied in vitro and compared with the affinity of cells of animals with delayed type allergy and with cytophilic antibodies. Spleen cells and peritoneal leucocytes from animals with allergy and with antibodies had an increased affinity for SE as shown by increased adherence or increased phagocytosis. This proved to be due to cytophilic antibodies. Lymph node cells also showed an increased adherence which was only partly due to cytophilic antibodies, as one group of cells showing adherence only appeared after active immunization (antibody forming cells?). The cells of animals with delayed type allergy without antibodies never showed adherence or increased phagocytosis. Thus when the presence of cytophilic antibodies was definitely excluded no evidence could be obtained that reticulo-endothelial cells of animals with delayed type allergy reacted in vitro with the antigen.