Inhibition of mouse liver cytochrome P-450 by gram-negative bacteria lipopolysaccharides.

The ability of bacterial endotoxins, of different origin, to modify the level of mouse liver cytochrome P-450 was investigated. Endotoxins, (lipopolysaccharides, LPSs) were isolated from Proteus, Escherichia, Salmonella, Bacteroides and Coxiella strains. The most potent inhibitor of cytochrome P-450 activity was S.

Prolonged survival of AVN Wistar rats with transplanted Yoshida sarcoma and increase of granular lymphocytes after administration of Bacillus firmus and their crude lipids.

Bacillus firmus is a Gram-positive, aerobic, sporulating, nonpathogenic air contaminant which, according to earlier findings, is a strong polyclonal activator of B lymphocytes. The crude lipids of this microbe induced significant resistance of mice against listerial infection. The administration of bacterin, like that of crude lipids obtained by the extraction of cell suspension with chloroform-methanol to rats, strain AVN Wistar, transplanted later with Yoshida sarcoma, significantly prolonged the survival of the animals in comparison with the control group.

Depression of cytochrome P-450 in mouse liver induced by fractions from Nocardia opaca.

We measured the liver cytochrome P-450 content of mice 24 h after they had been injected with the following immunoadjuvants: Nocardia opaca derivatives and peptidoglycans from several bacterial strains. The cell wall fraction was not active, the others diminished liver cytochrome P-450 levels. The dose-response activity varied with the bacterial origin of the peptidoglycans.

The influence of Propionibacterium acnes (Corynebacterium parvum) fractions on immune response in vivo.

Bacterin of Propionibacterium acnes (Corynebacterium parvum), its cellular fractions (lipids, fractions obtained by mechanical disruption and differential centrifugation, by phenol-water and pyridine extractions), and a polysaccharide from culture filtrate were prepared and tested in mice. The activation of RES by splenomegaly and hepatomegaly, prevention of listerial infection, prevention of the lethal effect of sarcoma 180, and depression of liver microsomal cytochrome P-450 were employed. The bacterin was effective in all tests.

Resistance to infection and activation of the monocyto-macrophage system caused by Bacillus firmus and its fractions.

Crude lipids isolated from Bacillus firmus, but not from other bacilli, were previously found to induce significant resistance against Listeria monocytogenes infection in mice. In this study, formaldehyde- and heat-killed bacterins of eight Bacillus species and some cellular fractions of B. firmus were prepared and tested for further immunomodulatory activities.