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Role of JAK2-STAT3 in TLR2-mediated tissue factor expression
Dae-Weon Park1, Ji Hyo Lyu, Jin-Sik Kim
1Department of Biochemistry and Molecular Biology, Aging-Associated Vascular Disease Research Center, College of Medicine, Yeungnam University, Daegu 705-802, Republic of Korea.
Journal of Cellular Biochemistry
|December 15, 2012
Summary
Pam3 CSK4 activates Toll-like receptor 2 (TLR2) to induce tissue factor (TF) expression in macrophages via the JAK2-STAT3 pathway. RGS2 acts as a negative regulator, targeting STAT3 to control this TF induction.
Area of Science:
- Immunology
- Molecular Biology
- Cardiovascular Research
Background:
- Tissue factor (TF) is crucial for blood vessel homeostasis but also implicated in atherosclerosis.
- Understanding TF regulation in macrophages is key to addressing vascular diseases.
Purpose of the Study:
- To elucidate the signaling mechanisms controlling TF expression in macrophages stimulated by Pam3 CSK4, a TLR2 ligand.
- To investigate the role of the JAK2-STAT3 pathway and RGS2 in this process.
Main Methods:
- Utilized Raw264.7 and bone marrow-derived macrophages (BMDM), including TLR2 knockout BMDM.
- Employed Toll-like receptor 2 (TLR2) ligand Pam3 CSK4, JAK inhibitors (pan-JAK, AG490), siRNA for JAK2 and STAT3, and RGS2 variants.
- Assessed TF and RGS2 expression, and STAT3 phosphorylation (S727).
Main Results:
- Pam3 CSK4 induced TF expression in macrophages, dependent on TLR2.
- The JAK2-STAT3 signaling pathway mediated Pam3 CSK4-induced TF expression.
- RGS2 negatively regulated TF expression by targeting STAT3 phosphorylation.
Conclusions:
- Pam3 CSK4-induced TF expression in macrophages is primarily regulated by the JAK2-STAT3 signaling axis.
- RGS2 functions as a negative feedback regulator in this pathway, impacting STAT3 activity.
- These findings offer insights into molecular mechanisms underlying TF-driven vascular pathology.
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