A Role of Macrophages in the Stimulation of Immune Responses by Adjuvants

Abstract Bordetella pertussis vaccine or beryllium sulfate proved to be potent adjuvants in increasing the antibody response to Maia squinado hemocyanin in mice. Antigen-containing macrophages treated with B. pertussis in vitro elicited much higher antibody titers when injected into mice than they did in the absence of the adjuvant. Lymph node cells treated in vitro with adjuvants and injected into irradiated mice gave the same antibody titers as they did in the absence of adjuvants. Hence in the system employed, adjuvants were shown to exert their enhancing effects on antibody-producing cells only after uptake by macrophages. Adjuvant-treated macrophages injected simultaneously with antigen-containing macrophages also led to increases in the immune response; thus adjuvant action did not require the presence of antigen and adjuvant in the same macrophage. The overall catabolism and retention of 131I-labeled hemocyanin in macrophages was not significantly altered in the presence of adjuvants.