A Toll-like receptor 2 ligand, Pam3CSK4, augments interferon-gamma-induced nitric oxide production via a physical association between MyD88 and interferon-gamma receptor in vascular endothelial cells

作者：Tsolmongyn Bilegtsaikhan; Koide Naoki; Jambalganiin Ulziisaikhan; Odkhuu Erdenezaya; Naiki Yoshikazu; Komatsu Takayuki; Yoshida Tomoaki; Yokochi Takashi^*

来源：Immunology, 2013, 140(3): 352-361.

DOI：10.1111/imm.12147

• interferon- receptor
• MyD88
• Pam3CSK4
• Toll-like receptor 2
• vascular endothelial cells

The effect of Pam3CSK4, a Toll-like receptor 2 (TLR2) ligand, on interferon- (IFN-) -induced nitric oxide (NO) production in mouse vascular endothelial END-D cells was studied. Pre-treatment or post-treatment with Pam3CSK4 augmented IFN--induced NO production via enhanced expression of an inducible NO synthase (iNOS) protein and mRNA. Pam3CSK4 augmented phosphorylation of Janus kinase 1 and 2, followed by enhanced phosphorylation of signal transducer and activator of transcription 1 (STAT1) at tyrosine 701. Subsequently, the enhanced STAT1 activation augmented IFN--induced IFN-regulatory factor 1 expression leading to the iNOS expression. Pam3CSK4 also induced the activation of p38 and subsequent phosphorylation of STAT1 at serine 727. A pharmacological p38 inhibitor abolished the augmentation of IFN--induced NO production by Pam3CSK4. Surprisingly, Pam3CSK4 enhanced a physical association of MyD88 and IFN- receptor. Together, these findings suggest that Pam3CSK4 up-regulates IFN- signalling in vascular endothelial cells via the physical association between MyD88 and IFN- receptor , and p38-dependent serine 727 STAT1 phosphorylation.

• 出版日期2013-11