Synthetic oligodeoxynucleotides induce MAP kinases activation in murine TIB-73 hepatocytes.
In this work we aimed to investigate the expression of TLR9 protein in the murine hepatocyte cell line TIB-73, compared to macrophage-like J774 cells, by Western blot analysis, and the role played by ERK 1/2 MAP kinase in the intracellular signals triggered by stimulation with CpG and non-CpG phosphodiester-ODN, and their more stable phosphorothioate-modified analogues.



TIB-73 hepatocytes express TLR9 protein. CpG and non-CpG ODN stimulation activated ERK 1/2 MAPK signal pathway in both hepatocytes and J774 murine macrophages. As expected, their phosphorothioate-CpG and non-CpG ODN analogues induced higher levels of ERK1/2 phosphorylation in TIB-73 cells, even higher than that induced in J774 cells under the same conditions. Phosphorylation of ERK 1/2 induced by synthetic ODN is dose-response dependent, being maximal at 100 microg/ml. Pretreatment of hepatocytes with an inhibitor of MEK-1 abrogated phosphorylation of ERK1/2 kinase.



TIB-73 hepatocytes constitutively express TLR9 and respond to synthetic ODN stimulation through a high ERK1/2 phosphorylation independent of CpG motifs. Slight differences were found on ERK1/2 activation when using phosphorothioate versus phosphodiester oligonucleotides.
Martín-Orozco
Elena
E
Department of Biochemistry and Molecular Biology B and Immunology, School of Medicine, University of Murcia, Murcia, Spain.
Chicano
Antonio
A
Ruiz-Alcaraz
Antonio J
AJ
Lizana
Ana
A
Martínez-Esparza
María
M
Hernández-Caselles
Trinidad
T
García-Peñarrubia
Pilar
P
D000818:Animals; D002460:Cell Line; D022781:Hepatocytes / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D009838:Oligodeoxyribonucleotides / Q000378:metabolism* / Q000494:pharmacology*; D009841:Oligonucleotides / Q000378:metabolism; D010766:Phosphorylation; D015398:Signal Transduction / Q000187:drug effects; D051217:Toll-Like Receptor 9 / Q000378:metabolism
C408982:CPG-oligonucleotide; D009838:Oligodeoxyribonucleotides; D009841:Oligonucleotides; D051217:Toll-Like Receptor 9; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases