Legionella pneumophila suppresses macrophage interleukin-12 production by activating the p42/44 mitogen-activated protein kinase cascade.
A possible involvement of the mitogen-activated protein (MAP) kinase cascade in the inhibition of macrophage interleukin-12 (IL-12) production by Legionella pneumophila infection was examined. The results of MAP kinase inhibition by p42/44 and p38 MAP kinase inhibitors and of p42/44 MAP kinase activity assays indicate that L. pneumophila infection of macrophages causes a selective inhibition of lipopolysaccharide-induced IL-12 production by activating the p42/44 MAP kinase cascade. In addition, it was also revealed that the p38 MAP kinase may be important for the production of IL-12 but not for the inhibition caused by L. pneumophila infection.
Department of Medical Microbiology and Immunology, University of South Florida College of Medicine, Tampa, Florida 33612, USA.
Kazuto
K
Matsunaga
Hiroyuki
H
Yamaguchi
Thomas W
TW
Klein
Herman
H
Friedman
Yoshimasa
Y
Yamamoto
D000818:Animals; D002460:Cell Line; D016753:Interleukin-10 / Q000096:biosynthesis; D018664:Interleukin-12 / Q000096:biosynthesis*; D016952:Legionella pneumophila / Q000276:immunology / Q000472:pathogenicity*; D020935:MAP Kinase Signaling System / Q000502:physiology*; D008264:Macrophages / Q000502:physiology*; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000502:physiology*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology*; D048051:p38 Mitogen-Activated Protein Kinases
D016753:Interleukin-10; D018664:Interleukin-12; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases