Fever range temperature promotes TLR4 expression and signaling in dendritic cells.

Abstract

Fever improves survival and shortens disease duration in microbial infections. However, the mechanisms of these beneficial responses still remain elusive. Toll-like receptors (TLRs) play important roles in sensing microbes invading and therefore we hypothesized that fever range temperature may enhance responsiveness of dendritic cells (DCs) to lipopolysaccharide (LPS) by promoting TLR4 expression and signaling. In this study, we found that pretreatment of DCs with 39.5 degrees C temperature can up-regulate TLR4 expression in DCs and enhances LPS-induced DC production of interleukins (IL) IL-6, IL-10 and IL-12 but not tumor necrosis factor alpha (TNF-alpha). Blockade of the autocrine action of IL-10 could increase LPS-induced TNF-alpha and IL-12 production in DCs. Further experiments confirmed that TLR4 ligation activates extracellular signal-regulated kinase (ERK), p38, and nuclear factor-kappaB pathways more potently in DCs pretreated with 39.5 degrees C. We conclude that fever range temperature can promote TLR4 expression and signaling in DCs, leading to enhancement of immune responses to inflammatory stimuli. These results might reveal a possible mechanistic explanation for the significance of fever in activating innate immune responses.

• Authors: Xiaoyi Yan, Fangming Xiu, Huazhang An, Xiaojian Wang, Jianli Wang, Xuetao Cao
• Journal: Life sciences (Life Sci) Vol. 80 Issue 4 Pg. 307-13 (Jan 02 2007) ISSN: 0024-3205 [Print] Netherlands
• PMID: 17084417 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Interleukins
• Lipopolysaccharides
• NF-kappa B
• RNA, Messenger
• Tlr4 protein, mouse
• Toll-Like Receptor 4
• Interleukin-10
• Extracellular Signal-Regulated MAP Kinases
• p38 Mitogen-Activated Protein Kinases

Topics

• Animals
• Dendritic Cells (drug effects, immunology, metabolism)
• Extracellular Signal-Regulated MAP Kinases (genetics, immunology, metabolism)
• Female
• Fever (immunology, metabolism, physiopathology)
• Gene Expression (drug effects)
• Interleukin-10 (agonists)
• Interleukins (genetics, metabolism)
• Lipopolysaccharides (pharmacology)
• Mice
• Mice, Inbred C57BL
• NF-kappa B (genetics, immunology, metabolism)
• RNA, Messenger (metabolism)
• Signal Transduction
• Toll-Like Receptor 4 (genetics, metabolism)
• Up-Regulation (immunology)
• p38 Mitogen-Activated Protein Kinases (genetics, immunology, metabolism)