Wdfy1 deficiency impairs Tlr3-mediated immune responses in vivo.
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ABSTRACT:
SUBMITTER: Yang Y
PROVIDER: S-EPMC7608371 | biostudies-literature | 2020 Sep
REPOSITORIES: biostudies-literature
Publications
Wdfy1 deficiency impairs Tlr3-mediated immune responses in vivo.
Yang Yang Y Hu Yun-Hong YH Liu Yu Y
Cellular & molecular immunology 20200512 9
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Project description:Toll-like receptors (TLRs) are pattern recognition receptors that sense a variety of pathogens, initiate innate immune responses, and direct adaptive immunity. All TLRs except TLR3 recruit the adaptor MyD88 to ultimately elicit inflammatory gene expression, whereas TLR3 and internalized TLR4 use TIR-domain-containing adaptor TRIF for the induction of type I interferon and inflammatory cytokines. Here, we identify the WD repeat and FYVE-domain-containing protein WDFY1 as a crucial adaptor protein in the TLR3/4 signaling pathway. Overexpression of WDFY1 potentiates TLR3- and TLR4-mediated activation of NF-κB, interferon regulatory factor 3 (IRF3), and production of type I interferons and inflammatory cytokines. WDFY1 depletion has the opposite effect. WDFY1 interacts with TLR3 and TLR4 and mediates the recruitment of TRIF to these receptors. Our findings suggest a crucial role for WDFY1 in bridging the TLR-TRIF interaction, which is necessary for TLR signaling.
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Project description:Hepatic expression of iron homeostasis genes and serum iron parameters predict the success of immunosuppression withdrawal following clinical liver transplantation, a phenomenon known as spontaneous operational tolerance. In experimental animal models, spontaneous liver allograft tolerance is established through a process that requires intra-hepatic lymphocyte activation and deletion. Our aim was to determine if changes in systemic iron status regulate intra-hepatic lymphocyte responses. We used a murine model of lymphocyte-mediated acute liver inflammation induced by Concanavalin A (ConA) injection employing mice fed with an iron-deficient (IrDef) or an iron-balanced diet (IrRepl). While the mild iron deficiency induced by the IrDef diet did not significantly modify the steady state immune cell repertoire and systemic cytokine levels, it significantly dampened inflammatory liver damage after ConA challenge. These findings were associated with a marked decrease in T cell and NKT cell activation following ConA injection in IrDef mice. The decreased liver injury observed in IrDef mice was independent from changes in the gut microflora, and was replicated employing an iron specific chelator that did not modify intra-hepatic hepcidin secretion. Furthermore, low-dose iron chelation markedly impaired the activation of isolated T cells in vitro. All together, these results suggest that small changes in iron homeostasis can have a major effect in the regulation of intra-hepatic lymphocyte mediated responses.
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Project description:BackgroundTo investigate the mechanism of Golgi matrix protein 130(GM130) regulating the antiviral immune response of TLR3 after herpes simplex virus type 1(HSV-1) infection of microglia cells. We explored the regulatory effects of berberine on the immune response mediated by GM130 and TLR3.MethodsAn in vitro model of HSV-1 infection was established by infecting BV2 cells with HSV-1.ResultsCompared to the uninfected group, the Golgi apparatus (GA) fragmentation and GM130 decreased after HSV-1 infection; TLR3 increased at 6 h and began to decrease at 12 h after HSV-1 infection; the secretion of interferon-beta(IFN-β), tumour necrosis factor alpha(TNF-α), and interleukin-6(IL-6) increased after infection. Knockdown of GM130 aggravated fragmentation of the GA and caused TLR3 to further decrease, and the virus titer also increased significantly. GM130 knockdown inhibits the increase in TLR3 and inflammatory factors induced by TLR3 agonists and increases the viral titer. Overexpression of GM130 alleviated fragmentation of the GA induced by HSV-1, partially restored the levels of TLR3, and reduced viral titers. GM130 overexpression reversed the reduction in TLR3 and inflammatory cytokine levels induced by TLR3 inhibitors. Therefore, the decrease in GM130 levels caused by HSV-1 infection leads to increased viral replication by inhibiting TLR3-mediated innate immunity. Berberine can protect the GA and reverse the downregulation of GM130, as well as the downregulation of TLR3 and its downstream factors after HSV-1 infection, reducing the virus titer.ConclusionsIn microglia, one mechanism of HSV-1 immune escape is disruption of the GM130/TLR3 pathway. Berberine protects the GA and enhances TLR3-mediated antiviral immune responses.
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2013-03-05 | E-GEOD-40812 | biostudies-arrayexpress
Project description:The objective of this study is to study the Toll-like receptor 3 (TLR3)-dependent gene expression in human fibroblast cells and peripheral blood mononuclear cells (PBMCs) Fibroblast cells and PBMCs from donors with autosomal recessive (AR) complete TLR3 deficiency and autosomal dominant (AD) partial TLR3 deficiency were collected for microarray analysis to measure the transcriptional responsiveness of TLR3 in fibroblast and PBMCs. A total of 3 healthy controls, 1 AD TLR3-deficient patient, 1 AR TLR3-deficient patient, 1 AR UNC-93B-deficient patient, 1 MyD88 deficient patien were used in this study. The fibroblast cells were cultured in DMEM medium supplemented with 10% fetal calf serum (FCS). The PBMCs were cultured in RPMI medium complemented with 10% FCS. Different kinetics (2 hours and 8 hours) of poly(I:C) (25ug/ml, purchased from Amersham) stimulations were performed, aiming to define TLR3-inducible genes in these human cells. A stimulation of IL-1β (20ng/ml, purchased from R&D system Inc.) was used as a positive activation control with same kinetics of stimulations. A total of one million cells per stimulation were used for fibroblasts, and around 1.5 million cells per stimulation for PBMCs.
2011-11-02 | E-GEOD-30951 | biostudies-arrayexpress
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Project description:The objective of this study is to study the Toll-like receptor 3 (TLR3)-dependent gene expression in human fibroblast cells and peripheral blood mononuclear cells (PBMCs)
2011-11-02 | GSE30951 | GEO