EFFECTS OF ENDOTOXINS FROM BACTEROIDES INTERMEDIUS AND ESCHERICHIA COLI ON CYTOTOXIC AND LYSOSOMAL ACTIVITY IN PERITONEAL MACROPHAGES FROM ENDOTOXIN RESPONDER AND LOW RESPONDER MOUSE STRAINS

Abstract

Johne. B., Myhrvold, V. & Mmland. B. Effects of endotoxins from Bucteroides intermedius and Esdicrichiu coli on cytotoxic and lysosomal activity in peritoneal macrophages from endotoxin responder and low responder mouse strains. Acta path. microbiol. immunol. scand. Sect. C, 95: 85-95, 1987. Peritoneal macrophages from normal mice strains (C3H/Tif and C57BL/6J) and from the endotoxin (lipopolysaccharide. LPS) low responder strain C3H/Hej were exposed to two structurally different endotoxins from Bucieroides interrnc~diics and Escherichia coli in vitro. lntracellular activity of a lysosomal enzyme (acid phosphatase) and macrophage mediated cytotoxic activity against a tumor cell line (L929) were tested. Both endotoxins caused increased levels of acid phosphatase activity in normal mice macrophages. No change was obtained in the C3H/Hej macrophages exposed to E. coli LPS; however, the B. inicwnc.diii.s LPS was able to strongly elevate intracellular enzyme level in the C3H/Hej low responder macrophages. Cytotoxic activities were investigated in macrophage supernatants and in co-cultures of stimulated macrophages and target cells. Cytotoxic activity evaluated by measuring release of radioactivity from "C-thymidine labelled tumor cells was increased with both endotoxins in normal mouse macrophages. but not in non-responder macrophages. When macrophage-mediated effects on tumor cells were tested by counting target cells left per culture, a reduction in target cell number was observed in endotoxin-treated low responder macrophage as well as in normal strain macrophage cultures more pronounced, however, in the normal strain. Cell contact between cytotoxic macrophages and target cells was 'verified by scanning electron microscopy. The results suggest that LPS effects on macrophages are dependent upon the functional parameters studied, and that the chemical composition of a particular LPS is important for its selective effects on macrophage functions.

Bioactive mechanism of Porphyromonas gingivalis lipid A

“…Lipopolysaccharide exhibits various endotoxic activities, such as pyrogenicity and lethal toxicity, as well as immunostimulatory activities including adjuvant activity and interferon induction (29, 30, 44). The endotoxic activities of P. gingivalis lipopolysaccharide and its lipid A are relatively weak when compared with those of enteric bacterium‐derived lipopolysaccharide and lipid A (12, 13, 23, 28, 46, 47, 49, 56). However, P. gingivalis lipopolysaccharide and lipid A were able to activate cells of lipopolysaccharide‐nonresponder C3H/HeJ mice, because of their unique chemical structures (6, 15, 23, 26, 27, 49, 52, 53).…”

“…The endotoxic activities of P. gingivalis lipopolysaccharide and its lipid A are relatively weak when compared with those of enteric bacterium‐derived lipopolysaccharide and lipid A (12, 13, 23, 28, 46, 47, 49, 56). However, P. gingivalis lipopolysaccharide and lipid A were able to activate cells of lipopolysaccharide‐nonresponder C3H/HeJ mice, because of their unique chemical structures (6, 15, 23, 26, 27, 49, 52, 53). A number of studies have reported that the endotoxic activities of P. gingivalis lipopolysaccharide and its lipid A, which include pyrogenicity in rabbits, Shwartzman reactions in rabbit skin and lethal toxicity in mice and chick embryos, but were weak (12, 13, 28, 46, 47, 49, 56).…”

“…It was demonstrated that Bacteroides lipopolysaccharide and lipid A, derived from different bacterial species that are similar to Bacteroides fragilis , such as P. gingivalis (formerly Bacteroides gingivalis ), Prevotella intermedia (formerly Bacteroides intermedius ), Prevotella oralis (formerly Bacteroides oralis ), Prevotella loescheii (formerly Bacteroides loescheii ) and Prevotella corporis (formerly Bacteroides corporis ), activate B lymphocytes and macrophages of C3H/HeJ mice (6, 11, 14, 15, 17, 20–23, 25–27, 49, 52, 53). We also reported that P. gingivalis lipopolysaccharide and lipid A have mitogenic effects and induce cytokine production by B lymphocytes from C3H/HeJ mice (12, 40, 41, 45).…”