The Effect of RES Blockade on Cellular Antibody Formation to Sheep Erythrocytes

Abstract

Processing of particulate antigens by cells of the reticuloendothelial system (RES) is an important step in antibody formation. RES blockade by colloidal substances may interfere with appearance of circulating antibody to a variety of antigens. Reticuloendothelial cell blockade was used to study the possible role of phagocytic cells in the immune response of mice to a single injection of sheep erythrocytes. Administration of 10 mg colloidal carbon (Pelikan) to a mouse resulted in a marked suppression in appearance of specific hemolytic antibody plaque forming cells (PFC) in the spleens of the treated animals. There was a suppression in both the total number of plaque forming cells in the spleen and the number of PFC per million viable nucleated cells. However, the day of peak antibody response was the same for carbon treated animals and for controls. Administration of carbon suspension 24 to 48 hr. prior to immunization of mice with sheep erythrocytes resulted in the most pronounced suppression, as compared to treatment with carbon on the same day as immunization, or at longer time periods prior to immunization. Injection of carbon 1 or 2 days after erythrocyte injection had little effect on the subsequent appearance of plaque forming cells. Injection of mice with carbon without red cells had no significant effect on the number of "background" plaque forming cells naturally present in the spleens of normal mice.