Toll-like receptor 2 (TLR2); TLR4; tumor necrosis factor-α (TNF-α)

Vibrio vulnificus is a pathogenic bacterium causing primary septicemia, which follows a classical septic shock pathway, including an overwhelming inflammatory cytokine response. In this study, we identified a putative lipoprotein of V. vulnificus, encoded by the ilpA gene, as one of the surface proteins that specifically reacted with the antibodies raised against outer membrane proteins of V. vulnificus. Using a mutant V. vulnificus in which its ilpA gene was knocked out, we found that IlpA is important in the production of interferon-γ in human peripheral blood mononuclear cells. Production of tumor necrosis factor-α and interleukin-6 is also induced by the recombinant IlpA (rIlpA) in human monocytes. Lipidation of the rIlpA was observed by in vivo labeling in Escherichia coli. Experiments using the mutant IlpA, which is unable to be modified by lipidation, indicate that the lipid moiety of this protein has an essential property for cytokine production in human cells. Pretreatment of monocytes with antibodies against Toll-like receptor 2 (TLR2) inhibited production of both tumor necrosis factor-α and interleukin-6. The role of TLR2 in IlpA-induced cytokine production was confirmed by an in vitro assay, in which only the TLR2-expressing cells showed a dramatic induction of nuclear factor-κB activity by rIlpA. In addition, rIlpA treatment resulted in induction of TLR2 transcription in human cells. In comparison with the wild type V. vulnificus, the ilpA mutant showed a reduced mortality in mice. These results demonstrate that IlpA of V. vulnificus functions as an immunostimulant to human cells via TLR2.

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Tumor necrosis factor α blockade treatment down-modulates the increased systemic and local expression of toll-like receptor 2 and toll-like receptor 4 in spondylarthropathy

Arthritis & Rheumatism ◽

10.1002/art.21155 ◽

2005 ◽

Vol 52 (7) ◽

pp. 2146-2158 ◽

Cited By ~ 92

Author(s):

Leen De Rycke ◽

Bernard Vandooren ◽

Elli Kruithof ◽

Filip De Keyser ◽

Eric M. Veys ◽

...

Keyword(s):

Tumor Necrosis Factor ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

Toll Like Receptor 2 ◽

Factor Α ◽

Necrosis Factor ◽

Local Expression

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#50 Gestational exposure of tumor necrosis factor-α (TNF-α) inhibitor drugs

Reproductive Toxicology ◽

10.1016/j.reprotox.2019.05.068 ◽

2019 ◽

Vol 88 ◽

pp. 149-150 ◽

Cited By ~ 1

Author(s):

Erkoseoglu Ilknur ◽

Kadioglu Mine ◽

Cavusoglu Irem ◽

Sisman Mulkiye ◽

Aran Turhan ◽

...

Keyword(s):

Tumor Necrosis Factor ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Gestational Exposure ◽

Tnf Α ◽

Factor Α ◽

Necrosis Factor

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Tumor necrosis factor α Inhibition for Alzheimer’s Disease

Journal of Central Nervous System Disease ◽

10.1177/1179573517709278 ◽

2017 ◽

Vol 9 ◽

pp. 117957351770927 ◽

Cited By ~ 43

Author(s):

Rudy Chang ◽

Kei-Lwun Yee ◽

Rachita K Sumbria

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Tumor Necrosis Factor ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Short Review ◽

Tnf Α ◽

Factor Α ◽

Ad Therapy ◽

Necrosis Factor

Tumor necrosis factor α (TNF-α) plays a central role in the pathophysiology of Alzheimer’s disease (AD). Food and Drug Administration–approved biologic TNF-α inhibitors are thus a potential treatment for AD, but they do not cross the blood-brain barrier. In this short review, we discuss the involvement of TNF-α in AD, challenges associated with the development of existing biologic TNF-α inhibitors for AD, and potential therapeutic strategies for targeting TNF-α for AD therapy.

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Tumor necrosis factor-α-associated lysosomal permeabilization is cathepsin B dependent

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00151.2002 ◽

2002 ◽

Vol 283 (4) ◽

pp. G947-G956 ◽

Cited By ~ 113

Author(s):

Nathan W. Werneburg ◽

M. Eugenia Guicciardi ◽

Steven F. Bronk ◽

Gregory J. Gores

Keyword(s):

Tumor Necrosis Factor ◽

Cathepsin B ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Fluorescent Protein ◽

Tnf Α ◽

Calcein Release ◽

Green Fluorescent ◽

Factor Α ◽

Necrosis Factor

Cathepsin B (Cat B) is released from lysososomes during tumor necrosis factor-α (TNF-α) cytotoxic signaling in hepatocytes and contributes to cell death. Sphingosine has recently been implicated in lysosomal permeabilization and is increased in the liver by TNF-α. Thus the aims of this study were to examine the mechanisms involved in TNF-α-associated lysosomal permeabilization, especially the role of sphingosine. Confocal microscopy demonstrated Cat B-green fluorescent protein and LysoTracker Red were both released from lysosomes after treatment of McNtcp.24 cells with TNF-α/actinomycin D, a finding compatible with lysosomal destabilization. In contrast, endosomes labeled with Texas Red dextran remained intact, suggesting lysosomes were specifically targeted for permeabilization. LysoTracker Red was released from lysosomes in hepatocytes treated with TNF-α or sphingosine in Cat B(+/+) but not Cat B(−/−) hepatocytes, as assessed by a fluorescence-based assay. With the use of a calcein release assay in isolated lysosomes, sphingosine permeabilized liver lysosomes isolated from Cat B(+/+) but not Cat B(−/−) liver. C6ceramide did not permeabilize lysosomes. In conclusion, these data implicate a sphingosine-Cat B interaction inducing lysosomal destabilization during TNF-α cytotoxic signaling.

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Prolyl Hydroxylase 3 (PHD3) Modulates Catabolic Effects of Tumor Necrosis Factor-α (TNF-α) on Cells of the Nucleus Pulposus through Co-activation of Nuclear Factor κB (NF-κB)/p65 Signaling

Journal of Biological Chemistry ◽

10.1074/jbc.m112.375964 ◽

2012 ◽

Vol 287 (47) ◽

pp. 39942-39953 ◽

Cited By ~ 51

Author(s):

Nobuyuki Fujita ◽

Shilpa S. Gogate ◽

Kazuhiro Chiba ◽

Yoshiaki Toyama ◽

Irving M. Shapiro ◽

...

Keyword(s):

Tumor Necrosis Factor ◽

Nucleus Pulposus ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Nuclear Factor Κb ◽

Nuclear Factor ◽

Co Activation ◽

Tnf Α ◽

Factor Α ◽

Necrosis Factor

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Tumor Necrosis Factor-α −308 Genotypes Influence Inflammatory Activity and TNF-α Serum Concentrations in Children with Juvenile Idiopathic Arthritis

The Journal of Rheumatology ◽

10.3899/jrheum.080615 ◽

2009 ◽

Vol 36 (4) ◽

pp. 837-842 ◽

Cited By ~ 18

Author(s):

ANA FILIPA MOURÃO ◽

JOANA CAETANO-LOPES ◽

PAULA COSTA ◽

HELENA CANHÃO ◽

MARIA JOSÉ SANTOS ◽

...

Keyword(s):

Juvenile Idiopathic Arthritis ◽

Tumor Necrosis Factor ◽

Disease Activity ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Inflammatory Activity ◽

Serum Concentrations ◽

Tnf Α ◽

Factor Α ◽

Necrosis Factor

Objective.Considering the relevance of tumor necrosis factor-α (TNF-α) in the pathophysiology of juvenile idiopathic arthritis (JIA), it is likely that polymorphisms in its promoter area may be relevant in disease susceptibility and activity. We investigated if clinical measures of JIA activity and TNF-α serum concentrations were associated with TNF-α −308 genotypes.Methods.Portuguese patients with JIA in 5 pediatric rheumatology centers were recruited consecutively, along with a control group of healthy subjects. Demographic and clinical data and blood samples were collected from each patient. DNA was extracted for analysis of TNF-α gene promoter polymorphisms at position −308 by restriction fragment-length polymorphism.Results.One hundred fourteen patients and 117 controls were evaluated; 57% of patients presented the oligoarticular subtype, 25% the polyarticular subtype, 8% the systemic subtype, and 9% had enthesitis-related arthritis and 5% psoriatic arthritis. Twenty-four percent of the patients presented the −308 GA/AA genotypes and 76% the −308 GG genotype, similar to findings in controls. Patients with the −308 GA/AA genotype had higher degree of functional impairment, erythrocyte sedimentation rate, 100-mm visual analog scale score for disease activity, and TNF-α levels compared to those with the −308 GG genotype.Conclusion.TNF-α −308 GA/AA genotypes were found to be related to higher inflammatory activity and worse measures of disease activity in Portuguese patients with JIA. They were not associated with susceptibility to JIA.

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Tumor Necrosis Factor α Regulates Responses to Nerve Growth Factor, Promoting Neural Cell Survival but Suppressing Differentiation of Neuroblastoma Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e07-06-0624 ◽

2008 ◽

Vol 19 (3) ◽

pp. 855-864 ◽

Cited By ~ 21

Author(s):

Yoshinori Takei ◽

Ronald Laskey

Keyword(s):

Nerve Growth Factor ◽

Growth Factor ◽

Tumor Necrosis Factor ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Neuroblastoma Cells ◽

Erk Activation ◽

Tnf Α ◽

Factor Α ◽

Necrosis Factor

Although nerve growth factor (NGF) promotes survival of neurons, tumor necrosis factor α (TNF-α) contributes to cell death triggered by NGF depletion, through TNF-α receptor (TNFR) 1. In contrast to this effect, TNF-α can promote neural cell survival via TNF-α receptor TNFR2. Although these findings demonstrate pivotal roles of TNF-α and NGF in cell fate decisions, cross-talk between these signaling pathways has not been clarified. We find that NGF can induce TNF-α synthesis through the nuclear factor-κB transcription factor. This provides a new basis for examining the cross-talk between NGF and TNF-α. Inhibition of TNFR2 shows opposite effects on two downstream kinases of NGF, extracellular signal-regulated kinase (Erk) and Akt. It increases Erk activation by NGF, and this increased activation induces differentiation of neuroblastoma cell lines. Reciprocally, inhibition of TNFR2 decreases Akt activation by NGF. Consistent with an essential role of Akt in survival signaling, inhibition of TNF-α signaling decreases NGF-dependent survival of neurons from rat dorsal root ganglia. Thus, NGF and NGF-induced TNF-α cooperate to activate Akt, promoting survival of normal neural cells. However, the NGF-induced TNF-α suppresses Erk activation by NGF, blocking NGF-induced differentiation of neuroblastoma cells. TNFR2 signaling could be a novel target to modulate cell responses to NGF.

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