LPS induces direct death of IFN-gamma primed murine embryonic hepatocyte, BNL CL2 cells in a TNF-alpha independent manner.
Although it has been well known that the role of LPS on liver damage is mediated through TNF-alpha, the mechanism by which LPS modulates the cytotoxicity of IFN-gamma on hepatocytes has not yet been clearly demonstrated. Here, we demonstrate that IFN-gamma mediated apoptosis in murine embryonic hepatocyte BNL CL2 cells is potentiated by the addition of LPS (0.5 microg/ml). Consistently, LPS markedly increases the catalytic activity of caspase 3-like protease but not caspase 1-like protease in IFN-gamma treated cells. In addition, TNF-alpha alone does not affect cell viability but rather it potentiates the cytotoxic effect of IFN-gamma on BNL CL2 cells. However, the cell viability of IFN-gamma/LPS treated cells is affected by the addition of polymyxin B but not by TNF binding protein I (TNF-BPI). These data suggest that the lipid moiety of LPS may mediate direct cytotoxicity of BNL CL2 cells in a TNF-alpha independent manner.
So
H S
HS
Department of Microbiology, Wonkwang University School of Medicine, Iksan, Chonbuk, Korea.
Jung
B H
BH
Yeum
S S
SS
Park
J S
JS
Kim
M S
MS
Lee
J H
JH
Chung
S Y
SY
Choi
S
S
Chae
H J
HJ
Kim
H R
HR
Ko
C B
CB
Chung
H T
HT
Park
R
R
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D004357:Drug Synergism; D004789:Enzyme Activation; D022781:Hepatocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D007371:Interferon-gamma / Q000378:metabolism* / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008099:Liver / Q000166:cytology / Q000196:embryology; D051379:Mice; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism* / Q000494:pharmacology
D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases