Nonspecific Macrophage Activation by Systemic Adjuvants

Abstract

Six systemic adjuvants: living bacillus Calmette-Guérin (BCG), hydrosoluble extracts from BCG and from Mycobacterium smegmatis, bacterial lipopolysaccharide, lentinan and levamisole, have been tested for their ability to induce macrophage activation in mice. The first four adjuvants mentioned increase phosphatase activity of peritoneal macrophages and make them nonspecifically cytotoxic for tumor cells in vitro. The intensity of these phenomena vary with route and time of administration. In contrast, lentinan and levamisole depress both these macrophage activities. Living BCG, extracts from BCG and from M. smegmatis, and the lipopolysaccharide increase the cytotoxic potential of normal macrophages in vitro, suggesting that these agents may exert a direct action on macrophages. Levamisole did not activate normal macrophages in vitro. The existence of a correlation between the capacity of adjuvants to stimulate macrophage tumoricidal activity and their efficiency in active cancer immunotherapy is discussed.

Cytotoxicity of rat macrophages activated by persistent or biodegradable bacterial cell walls

“…Whereas macrophages containing group A cell walls retain these characteristics for several weeks in culture, macrophages that have phagocytized group D cell walls revert to a normal appearance after 2 to 3 days. The inability to degrade and eliminate group A cell walls (21) is related to the perpetuation of these changes in macrophages, which are similar to those described by others (1,2,7,10,11).…”

“…Our purpose is to determine if macrophages that have ingested cell wall material could function as effector cells in the tissue injury induced by group A cell walls and whether the susceptibility or resistance of inbred rat strains can be related to the cytotoxic potential of their macrophages. Our observation on the importance of phagocytized material that is persistent but not toxic for the macrophage also helps to define some of the requirements for nonspecific immunity attained through macrophages activated by other agents such as BCG and endotoxin (1,2).…”

Monoclonal Antibody to an Alveolar Macrophage Surface Antigen in Hamsters

“…Cells were obtained by peritoneal lavage 3 to 5 days after the injection. Peritoneal macrophages were stimulated in vivo by injecting 1 mg BCG (University of Illinois) intraperitoneally (36). Peritoneal macrophages were harvested 2 to 3 wk later.…”