Interaction between LPS-induced NO production and IDO activity in mouse peritoneal cells in the presence of activated Valpha14 NKT cells.
In this study, we demonstrated that lipopolysaccharide (LPS) markedly increased nitric oxide (NO) production and indoleamine 2,3-dioxygenase (IDO) activity in mouse peritoneal cells in the presence of activated Valpha14 natural killer T cells. Moreover, LPS-induced NO production in peritoneal cells from IDO-knockout (KO) mice was more increased than that from wild-type mice. However, there was no significant difference in the expression of inducible nitric oxide synthase (iNOS) mRNA and protein between the wild-type and IDO-KO mice. No significant difference was also observed in the ratio of CD3- and DX5-positive cells and F4/80- and TLR4-positive cells in peritoneal cells between the wild-type and IDO-KO mice. Since the IDO activity was enhanced by an NO inhibitor, NO may be post-translationally consumed by inhibiting the IDO activity. IDO is well known to play an important role in immunosuppression during inflammatory disease. Therefore, the inhibition of IDO by NO may exacerbate inflammation in the peritoneal cavity.
Ohtaki
Hirofumi
H
Department of Informative Clinical Medicine, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu 501-1194, Japan.
Ito
Hiroyasu
H
Ando
Kazuki
K
Ishikawa
Tetsuya
T
Hoshi
Masato
M
Tanaka
Ryo
R
Osawa
Yosuke
Y
Yokochi
Takashi
T
Moriwaki
Hisataka
H
Saito
Kuniaki
K
Seishima
Mitsuru
M
D000818:Animals; D005699:Galactosylceramides / Q000276:immunology; D007108:Immune Tolerance; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000235:genetics / Q000378:metabolism*; D007371:Interferon-gamma / Q000276:immunology; D008070:Lipopolysaccharides / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D055611:Natural Killer T-Cells / Q000276:immunology*; D009569:Nitric Oxide / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D010537:Peritoneum / Q000201:enzymology / Q000276:immunology*; D010538:Peritonitis / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology
D005699:Galactosylceramides; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D008070:Lipopolysaccharides; D016693:Receptors, Antigen, T-Cell, alpha-beta; C493154:alpha-galactosylceramide; D009569:Nitric Oxide; D007371:Interferon-gamma; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse