Abstract
Gram-positive bacterial products such as peptidoglycan (PGN) and lipoteichoic acid (LTA) are potent stimulators of innate inflammatory responses. We previously reported that lipopolysaccharide (LPS), a major biologically active agent of gram-negative bacteria, induces a proinflammatory response via the Toll-like receptor (TLR) 4 in hepatic stellate cells (HSCs). Here we investigated the mechanism of proinflammatory action by PGN and LTA in activated human HSCs. Following treatment with either TNF-α or IL-1β, expression of TLR2 and CD14 was determined by real-time PCR and Western blotting. NF-κB activation was assessed by NF-κB-driven luciferase assay and electrophoretic mobility shift assay. Interleukin-8 (IL-8) from culture supernatant was measured by ELISA. Activated human HSCs express TLR2 and CD14, which are receptors for PGN and LTA signaling. TNF-α and IL-1β significantly upregulated the expression of TLR2 mRNA and protein in HSCs. PGN and LTA induced NF-κB activation and stimulated production of IL-8 in HSCs. Pretreatment with TNF-α or IL-1β augmented NF-κB activation and IL-8 production in response to PGN or LTA. Both PGN- and LTA-induced NF-κB activation and IL-8 secretion were completely inhibited by anti-TLR2 blocking antibody (T2.5). These findings suggest that TNF-α or IL-1β primed HSCs enhance the production of IL-8 in response to PGN and LTA through augmentation of the TLR2 system.
| Original language | English |
|---|---|
| Pages (from-to) | 676-686 |
| Number of pages | 11 |
| Journal | Laboratory Investigation |
| Volume | 86 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - 2006 Jul 1 |
Fingerprint
All Science Journal Classification (ASJC) codes
- Pathology and Forensic Medicine
- Molecular Biology
- Cell Biology
Cite this
}
Hepatic stellate cells primed with cytokines upregulate inflammation in response to peptidoglycan or lipoteichoic acid. / Paik, Yong Han; Lee, Kwan Sik; Lee, Hyun Jin; Yang, Kyung Min; Lee, Se Jun; Lee, Dong Ki; Han, Kwang Hyub; Chon, Chae Yoon; Lee, Sang In; Moon, Young Myoung; Brenner, David A.
In: Laboratory Investigation, Vol. 86, No. 7, 01.07.2006, p. 676-686.Research output: Contribution to journal › Article
TY - JOUR
T1 - Hepatic stellate cells primed with cytokines upregulate inflammation in response to peptidoglycan or lipoteichoic acid
AU - Paik, Yong Han
AU - Lee, Kwan Sik
AU - Lee, Hyun Jin
AU - Yang, Kyung Min
AU - Lee, Se Jun
AU - Lee, Dong Ki
AU - Han, Kwang Hyub
AU - Chon, Chae Yoon
AU - Lee, Sang In
AU - Moon, Young Myoung
AU - Brenner, David A.
PY - 2006/7/1
Y1 - 2006/7/1
N2 - Gram-positive bacterial products such as peptidoglycan (PGN) and lipoteichoic acid (LTA) are potent stimulators of innate inflammatory responses. We previously reported that lipopolysaccharide (LPS), a major biologically active agent of gram-negative bacteria, induces a proinflammatory response via the Toll-like receptor (TLR) 4 in hepatic stellate cells (HSCs). Here we investigated the mechanism of proinflammatory action by PGN and LTA in activated human HSCs. Following treatment with either TNF-α or IL-1β, expression of TLR2 and CD14 was determined by real-time PCR and Western blotting. NF-κB activation was assessed by NF-κB-driven luciferase assay and electrophoretic mobility shift assay. Interleukin-8 (IL-8) from culture supernatant was measured by ELISA. Activated human HSCs express TLR2 and CD14, which are receptors for PGN and LTA signaling. TNF-α and IL-1β significantly upregulated the expression of TLR2 mRNA and protein in HSCs. PGN and LTA induced NF-κB activation and stimulated production of IL-8 in HSCs. Pretreatment with TNF-α or IL-1β augmented NF-κB activation and IL-8 production in response to PGN or LTA. Both PGN- and LTA-induced NF-κB activation and IL-8 secretion were completely inhibited by anti-TLR2 blocking antibody (T2.5). These findings suggest that TNF-α or IL-1β primed HSCs enhance the production of IL-8 in response to PGN and LTA through augmentation of the TLR2 system.
AB - Gram-positive bacterial products such as peptidoglycan (PGN) and lipoteichoic acid (LTA) are potent stimulators of innate inflammatory responses. We previously reported that lipopolysaccharide (LPS), a major biologically active agent of gram-negative bacteria, induces a proinflammatory response via the Toll-like receptor (TLR) 4 in hepatic stellate cells (HSCs). Here we investigated the mechanism of proinflammatory action by PGN and LTA in activated human HSCs. Following treatment with either TNF-α or IL-1β, expression of TLR2 and CD14 was determined by real-time PCR and Western blotting. NF-κB activation was assessed by NF-κB-driven luciferase assay and electrophoretic mobility shift assay. Interleukin-8 (IL-8) from culture supernatant was measured by ELISA. Activated human HSCs express TLR2 and CD14, which are receptors for PGN and LTA signaling. TNF-α and IL-1β significantly upregulated the expression of TLR2 mRNA and protein in HSCs. PGN and LTA induced NF-κB activation and stimulated production of IL-8 in HSCs. Pretreatment with TNF-α or IL-1β augmented NF-κB activation and IL-8 production in response to PGN or LTA. Both PGN- and LTA-induced NF-κB activation and IL-8 secretion were completely inhibited by anti-TLR2 blocking antibody (T2.5). These findings suggest that TNF-α or IL-1β primed HSCs enhance the production of IL-8 in response to PGN and LTA through augmentation of the TLR2 system.
UR - http://www.scopus.com/inward/record.url?scp=33745129374&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33745129374&partnerID=8YFLogxK
U2 - 10.1038/labinvest.3700422
DO - 10.1038/labinvest.3700422
M3 - Article
C2 - 16619004
AN - SCOPUS:33745129374
VL - 86
SP - 676
EP - 686
JO - Laboratory Investigation
JF - Laboratory Investigation
SN - 0023-6837
IS - 7
ER -