Synergistic interaction between C5a and NOD2 signaling in the regulation of chemokine expression in RAW 264.7 macrophages.
Adv Biosci Biotechnol
; 4(8C): 30-37, 2013 Aug.
Article
in En
| MEDLINE
| ID: mdl-24634797
ABSTRACT
The innate immune response is a complex process involving multiple pathogen-recognition receptors, including toll-like receptors (TLRs) and nucleotide-binding oligomerization domain (NOD)-like receptors. Complement is also a critical component of innate immunity. While complement is known to interact with TLR-mediated signals, the interactions between NOD-like receptors and complement are not well understood. Here we report a synergistic interaction between C5a and Nod2 signaling in RAW 264.7 macrophages. Long-term treatment with muramyl dipeptide (MDP), a NOD2 ligand, enhanced C5a-mediated expression of chemokine mRNAs in RAW 264.7 cells. This response was dependent on NOD2 expression and was associated with a decrease in expression of C5L2, a receptor for C5a which acts as a negative modulator of C5a receptor (C5aR) activity. MDP amplified C5a-mediated phosphorylation of p38 MAPK. Treatment of RAW264.7 cells with an inhibitor of p38 attenuated the synergistic effects of C5a on MDP-primed cells on MIP-2, but not MCP-1, mRNA. In contrast, inhibition of AKT prevented C5a stimulation of MCP-1, but not MIP-2, mRNA, in MDP-primed cells. Taken together, these data demonstrated a synergistic interaction between C5a and NOD2 in the regulation of chemokine expression in macrophages, associated with a down-regulation of C5L2, a negative regulator of C5a receptor activity.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Adv Biosci Biotechnol
Year:
2013
Document type:
Article
Affiliation country:
Estados Unidos
Publication country:
EEUU
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ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
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USA