Search results for "toll"
showing 10 items of 324 documents
SARS CoV2 infection _The longevity study perspectives
2021
Graphical abstract
Can the TLR-4-mediated signaling pathway be "a key inflammatory promoter for sporadic TAA"?
2014
Thoracic aorta shows with advancing age various changes and a progressive deterioration in structure and function. As a result, vascular remodeling (VR) and medial degeneration (MD) occur as pathological entities responsible principally for the sporadic TAA onset. Little is known about their genetic, molecular, and cellular mechanisms. Recent evidence is proposing the strong role of a chronic immune/inflammatory process in their evocation and progression. Thus, we evaluated the potential role of Toll like receptor- (TLR-) 4-mediated signaling pathway and its polymorphisms in sporadic TAA. Genetic, immunohistochemical, and biochemical analyses were assessed. Interestingly, the rs4986790 TLR4…
Mast cells as rapid innate sensors of cytomegalovirus by TLR3/TRIF signaling-dependent and -independent mechanisms
2014
The succinct metaphor, ‘the immune system's loaded gun', has been used to describe the role of mast cells (MCs) due to their storage of a wide range of potent pro-inflammatory and antimicrobial mediators in secretory granules that can be released almost instantly on demand to fight invaders. Located at host–environment boundaries and equipped with an arsenal of pattern recognition receptors, MCs are destined to be rapid innate sensors of pathogens penetrating endothelial and epithelial surfaces. Although the importance of MCs in antimicrobial and antiparasitic defense has long been appreciated, their role in raising the alarm against viral infections has been noted only recently. Work on cy…
TLR4 upregulation underpins airway neutrophilia in smokers with chronic obstructive pulmonary disease and acute respiratory failure
2010
Activation of Toll-like receptors (TLR) seems to be involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). Upon TLR activation the release of defensins, including human beta defensin 2 (HBD-2), may occur. In this study, we explored the innate responses in patients with respiratory failure, with and without COPD, requiring intubation and mechanical ventilation. Mini-bronchoalveolar lavage (mini-BAL) samples were collected from nonsmoker subjects without COPD (n = 10), smokers without COPD (n = 6), and smokers with COPD (n = 15). TLR4, TLR2, and HBD-2 expression was evaluated by immunocytochemistry; interleukin (IL)-8, IP-10, and HBD-2 concentrations were evaluated by e…
Toll-like receptor 5 deficiency exacerbates cardiac injury and inflammation induced by myocardial ischaemia-reperfusion in the mouse
2015
Myocardial ischaemia-reperfusion (MIR) triggers a sterile inflammatory response important for myocardial healing, but which may also contribute to adverse ventricular remodelling. Such inflammation is initiated by molecular danger signals released by damaged myocardium, which induce innate immune responses by activating toll-like receptors (TLRs). Detrimental roles have been recently reported for TLR2, TLR3 and TLR4. The role of other TLRs is unknown. We therefore evaluated the role of TLR5, expressed at high level in the heart, in the development of myocardial damage and inflammation acutely triggered by MIR. TLR5−/− and wild-type (WT) mice were exposed to MIR (30 min ischaemia, 2 h reperf…
Synergistic effect between amoxicillin and TLR ligands on dendritic cells from amoxicillin-delayed allergic patients.
2013
Journal Article; Amoxicillin, a low-molecular-weight compound, is able to interact with dendritic cells inducing semi-maturation in vitro. Specific antigens and TLR ligands can synergistically interact with dendritic cells (DC), leading to complete maturation and more efficient T-cell stimulation. The aim of the study was to evaluate the synergistic effect of amoxicillin and the TLR2, 4 and 7/8 agonists (PAM, LPS and R848, respectively) in TLR expression, DC maturation and specific T-cell response in patients with delayed-type hypersensitivity (DTH) reactions to amoxicillin. Monocyte-derived DC from 15 patients with DTH to amoxicillin and 15 controls were cultured with amoxicillin in the pr…
Molecular basis of endothelial dysfunction in sepsis.
2003
Sepsis is one of the major causes of mortality in critically ill patients and develops as a result of the host response to infection. A complex network of events is set into motion in the body by the infection and results in the pathogenesis of sepsis. This review article focuses on the molecular mechanisms and components involved in the pathogenesis of sepsis with a major emphasis on the endothelium. This includes sepsis-inducing bacterial components (e.g. endotoxins), cellular targets of these molecules and their responses, host reactions, intracellular and cytokine networks, individual susceptibility and new therapeutic targets in sepsis treatment.
CANDIDA ALBICANS INDUCES SELECTIVE DEVELOPMENT OF MACROPHAGES AND MONOCYTE DERIVED DENDRITIC CELLS BY A TLR2 DEPENDENT SIGNALLING
2011
As TLRs are expressed by haematopoietic stem and progenitor cells (HSPCs), these receptors may play a role in haematopoiesis in response to pathogens during infection. We have previously demonstrated that in in vitro defined conditions inactivated yeasts and hyphae of Candida albicans induce HSPCs proliferation and differentiation towards the myeloid lineage by a TLR2/MyD88 dependent pathway. In this work, we showed that C. albicans invasive infection with a low virulence strain results in a rapid expansion of HSPCs (identified as LKS cells: Lin(-) c-Kit(+) Sca-1(+) IL-7R alpha(-)), that reach the maximum at day 3 post-infection. This in vivo expansion of LKS cells in TLR2(-/-) mice was del…
Mild-stretch mechanical ventilation upregulates toll-like receptor 2 and sensitizes the lung to bacterial lipopeptide.
2011
Introduction Mechanical ventilation (MV) could prime the lung toward an inflammatory response if exposed to another insult such as bacterial invasion. The underlying mechanisms are not so far clear. Toll-like receptors (TLRs) allow the host to recognize selectively bacterial pathogens and in turn to trigger an immune response. We therefore hypothesized that MV modulates TLR2 expression and in turn modifies responsiveness to agonists such as bacterial lipopeptide (BLP). Method Both in vitro and in vivo experiments were conducted. First, TLR2 expression and protein were measured in the A549 pulmonary epithelial cell line submitted to 8-hour cyclic stretch (20% elongation; 20/minute rate). Aft…
Enhanced glomerular Toll-like receptor 4 expression and signaling in patients with type 2 diabetic nephropathy and microalbuminuria
2014
Toll-like receptor 4 (TLR4), a component of the innate immune system, is recognized to promote tubulointerstitial inflammation in overt diabetic nephropathy (DN). However, there is no information on immune activation in resident renal cells at an early stage of human DN. In order to investigate this, we studied TLR4 gene and protein expression and TLR4 downward signaling in kidney biopsies of 12 patients with type 2 diabetes and microalbuminuria, and compared them with 11 patients with overt DN, 10 with minimal change disease (MCD), and control kidneys from 13 patients undergoing surgery for a small renal mass. Both in microalbuminuria and in overt DN, TLR4 mRNA and protein were overexpress…