The toll-like receptors (TLRs) are a key component of host defense in the respiratory epithelium. Cigarette smoking is associated with increased susceptibility to infection, while COPD is characterised by bacterial colonisation and infective exacerbations. We found reduced TLR4 gene expression in the nasal epithelium of smokers compared with non-smoking controls, while TLR2 expression was uncha...

OBJECTIVE Helicobacter pylori (Hp) is recognized by TLR4 and TLR2 receptors, which trigger the activation of genes involved in the host immune response. Thus, we evaluated the effect of eradication therapy on TLR2 and TLR4 mRNA and protein expression in H. pylori-infected chronic gastritis patients (CG-Hp+) and 3 months after treatment. METHODS A total of 37 patients CG-Hp+ were evaluated. Th...

Objective(s): High Mobility Group Box1 (HMGB1) is a nonhistone, DNA-binding protein that serves a crucial role in regulating gene transcription and is involved in a variety of proinflammatory, extracellular activities. The aim of this study was to explore whether HMGB1 stimulation can up-regulate the expression of Toll-like Receptor 2 (TLR2) and Toll-like Receptor 4 (TLR4) on macrophages from p...

UNLABELLED Toll-like receptor 4 is thought to have a primary role in host defense against Escherichia coli bladder colonization, based on mouse models of urinary tract infection using C3H/HeJ female mice. This strain carries a point mutation in the Tlr4 gene, which renders the mice unresponsive to lipopolysaccharide (LPS) and thus limits the bladder inflammatory response and infection resolutio...

TLR4 is the receptor for the Gram-negative bacterial cell wall component LPS. TLR4 signaling is controlled by both positive and negative regulators to balance optimal immune response and potential sepsis. Unchecked TLR4 activation might result in autoimmune diseases, a hypothesis that has not been formally resolved. In this study, we found that TLR4 signaling to LPS can be positively enforced b...

BACKGROUND Human nasopharynx is often colonized by potentially pathogenic bacteria. Gene polymorphisms in mannose-binding lectin (MBL), toll-like receptor (TLR) 2 and TLR4 have been reported. The present study aimed to investigate possible association between nasopharyngeal bacterial colonization and gene polymorphisms of MBL, TLR2 and TLR4 in healthy infants. METHODOLOGY/PRINCIPAL FINDINGS F...

TLR4 is crucial for macrophage responses to LPS. It is less clear whether TLR4 may also transduce signals from host factors, and if so, with what consequences. Immortalized bone marrow-derived macrophage cell lines, termed T4Cr and T4ko, were established from TLR4null strains, C57BL/10ScNCr and TLR4 knockout mice, respectively. Multiple transfections and selections were conducted to stably intr...

The lumenal surface of the colonic epithelium is continually exposed to Gram-negative commensal bacteria and LPS. Recognition of LPS by Toll-like receptor (TLR)-4 results in proinflammatory gene expression in diverse cell types. Normally, however, commensal bacteria and their components do not elicit an inflammatory response from intestinal epithelial cells (IEC). The aim of this study is to un...

Toll-like receptor 4 (TLR4) is important in promoting the immune response in various cancers. Recently, TLR4 is highly expressed in a stage-dependent manner in gastric cancer, but the regulatory mechanism of TLR4 expression has been not elucidated it. Here, we investigated the mechanism underlying regulation of TLR4 expression through promoter methylation and histone modification between transc...

BACKGROUND Inflammation in skeletal muscle is implicated in the pathogenesis of insulin resistance and cachexia but why uremia up-regulates pro-inflammatory cytokines is unknown. Toll-like receptors (TLRs) regulate locally the innate immune responses, but it is unknown whether in chronic kidney disease (CKD) TLR4 muscle signalling is altered. The aim of the study is to investigate whether in CK...