Effects of endotoxin tolerance on Propionibacterium acnes-primed lipopolysaccharide hepatic injury

• Published in: The Journal of surgical research 2003-06, Vol.112 (1), p.102-110
• Main Authors: Margenthaler, Julie A, Landeros, Keith, Kataoka, Masaaki, Eilers, Mark, Ku, Grace, Flye, M Wayne
• Format: Article
• Language: English
• Subjects: Animals; Cytokines - blood; Cytokines - genetics; Gram-Positive Bacterial Infections - immunology; Gram-Positive Bacterial Infections - mortality; Gram-Positive Bacterial Infections - pathology; Leukocytes, Mononuclear - immunology; Leukocytes, Mononuclear - metabolism; Lipopolysaccharides - pharmacology; Liver Diseases - immunology; Liver Diseases - microbiology; Liver Diseases - pathology; Male; Mice; Mice, Inbred C57BL; Propionibacterium acnes; RNA, Messenger - analysis; Spleen - cytology; Spleen - immunology; Survival Analysis
• ISSN: 0022-4804
• DOI: 10.1016/S0022-4804(03)00133-1

Prior administration of the Gram-positive bacteria Propionibacterium acnes (PA) results in hypersensitivity and hepatocyte necrosis to a subsequent low dose of lipopolysaccharide (LPS). Endotoxin tolerance has been shown to prevent lethality after ischemia/reperfusion injuries, sepsis, and endotoxic shock. We investigated whether prior induction of LPS tolerance could prevent subsequent PA-priming and LPS-induced death. The levels of known effector cytokines possibly responsible for these changes were measured. C57BL/6 (B6) mice were given heat-killed PA (0.5 mg/mouse) followed 7 days later by LPS (20 microg/mouse). In parallel experiments, B6 mice were pretreated with a single 20 microg/mouse dose of LPS (lethal dose = 800 microg/mouse) 7 days prior to PA priming. Animal survival, liver and spleen weights, and histology were examined. Cytokine levels of the inflammatory cytokines interferon-alpha, tumor necrosis factor-gamma, interleukin (IL)-6, and IL-12 and the anti-inflammatory cytokines IL-4 and IL-10 were measured by enzyme-linked immunosorbent assay and by reverse-transcription polymerase chain reaction. Hepatomegaly, splenomegaly, and hepatocyte necrosis with death developed in all PA-primed B6 mice challenged with LPS. However, 83% of B6 mice given a tolerizing dose of LPS prior to PA survived (P < 0.01) without any increase in liver or spleen weights and without histological evidence of necrosis. Markedly decreased in vivo and in vitro inflammatory (interferon-alpha, tumor necrosis factor-gamma, IL-6, and IL-12) cytokine levels corresponded with survival in the LPS-tolerant mice. Endotoxin tolerance and subsequent survival were also associated with an increase in anti-inflammatory (IL-4 and IL-10) mRNA expression. Lethal PA-primed LPS-induced hepatic injury can be prevented by administering a tolerizing dose of LPS prior to PA-priming. LPS protects the liver by preventing hepatic mononuclear cellular infiltration, reducing the production of the toxic proinflammatory cytokines, and inducing the production of endogenous anti-inflammatory cytokines.