The gene coding for the endotoxin receptor TLR4 (toll-like receptor 4) has been sequenced recently, and the polymorphic spectrum of the gene has been elucidated (1). A polymorphism in the gene affects the inflammatory response to lipopolysaccharide (LPS) (2,3), with impact on the risk of gramnegative infections and septic shock (4,5). We have analyzed two cosegregating mutations in the gene reg...

Intestinal epithelial cells (IECs) are continuously exposed to large numbers of commensal bacteria but are relatively insensitive to them, thereby averting an excessive inflammatory reaction. We have previously reported that the hyporesponsiveness of a human IEC line to LPS was primarily the result of a down-regulation of TLR4 gene transcription through epigenetic mechanisms. In the present stu...

TLR4 is the main recognition receptor of bacterial lipopolysaccharides, which play an important role in innate and adaptive immunity. We used real-time PCR to analyze the tissue expression profile and differential expression of TLR4 in 4 pig populations (Escherichia coli F18-resistant Sutai, E. coli F18-sensitive Sutai, Large White, Meishan), in order to determine the role that the TLR4 gene pl...

Background: Common variable immunodeficiency (CVID) is a primary immune disorder associated with hypogammaglobulinemia, recurrent infections and autoimmune diseases. CVID patients are frequently in contact with infectious pathogens leading to the activation of innate immunity through Toll-like receptors (TLR) affecting adaptive immunity. The aim of the present study was to test the immunomedula...

TLR4 gene, vitally linked to resistance infection with Salmonella enteric serovar Typhimurium in chickens, was chosen as a candidate gene for this investigation assess the probable impact of microsatellite genotypes on relative expression gene. Our study documented variable level tissue bursa RIR chicken encoded different genotypes. The DD and CC MCW0330 demonstrated numerically higher mRNA tha...

Intestinal epithelial cells (IECs) are continuously exposed to large numbers of commensal bacteria but are relatively insensitive to them, thereby averting an excessive inflammatory reaction. In this study, we show that the low responsiveness of human IEC lines to LPS was mainly brought about by a down-regulation of TLR4 gene transcription. Additionally, the presence of an IEC-specific represso...

Toll-like receptors (TLRs) are key factors in the innate immune system and initiate an inflammatory response to foreign pathogens, such as bacteria, fungi and viruses. TLR4-mediated signaling has been implicated in tumor cell proliferation and apoptosis in numerous cancers. The present study aimed to investigate the biological effect of TLR4 on the proliferation and apoptosis of human liver can...

We hypothesized that PU.1 and PU.1 interacting proteins (PIP) binding to the Toll-like receptor 4 (TLR4) promoter is involved in endotoxin-induced upregulation of TLR4 gene expression. Our results employing chromatin immunoprecipitation assays indicate that PU.1 binds to the murine TLR4 promoter both in macrophage cells and, most importantly, in whole lung tissue. Treatment of RAW 264.7 cells w...

We previously reported that Toll-like receptor-2 (TLR2) agonists induce expression of a more limited repertoire of pro-inflammatory genes than TLR4 agonists. Murine macrophages stimulated with the TLR4 agonist, Escherichia coli lipopolysaccharide, induced signal transducer and activator of transcription 1 ('STAT1') tyrosine phosphorylation that was secondary to the autocrine/paracrine action of...