scholarly journals FRI0016 R835, A NOVEL IRAK1/4 DUAL INHIBITOR IN CLINICAL DEVELOPMENT, BLOCKS TOLL-LIKE RECEPTOR 4 (TLR4) SIGNALING IN HUMAN AND MOUSE

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 579.1-579
Author(s):  
C. Lamagna ◽  
C. Gundel ◽  
M. Chan ◽  
C. Young ◽  
S. Braselmann ◽  
...  
Keyword(s):  
Whole Blood ◽  
Cytokine Production ◽  
Interleukin 1 ◽  
Clinical Development ◽  
Innate Immune ◽  
Toll Like Receptor ◽  
Serum Cytokine ◽  
Tlr4 Signaling ◽  
Molecule Inhibitor ◽  
Human And Mouse

Background:Toll-Like Receptors (TLR) and Interleukin-1 Receptors (IL-1R) play a critical role in the innate immune response as microbial sensors, providing a bridge between the innate and adaptive immunity (1). Interleukin receptor associated kinases (IRAK) 1 and 4 are serine/threonine kinases that are essential for signaling downstream of most TLRs and IL-1Rs and the resulting production of pro-inflammatory cytokines (2). Suppression of TLR and IL-1R signaling through inhibition of IRAK1/4 kinases is a promising therapeutic approach for the treatment of inflammatory and autoimmune diseases.Objectives:The aim of the study was to characterize the effects of R835, a novel small molecule inhibitor of IRAK1/4, on TLR4 signaling.Methods:R835 was identified in cell-based assays measuring cytokine production induced by LPS (TLR4 ligand). Inhibition of IRAK1 and IRAK4 kinases by R835 was confirmed in biochemical assays and cell lysates. The ability of R835 to inhibit TLR4 signaling was further evaluated in human and mouse whole blood assays. R835 was tested in a mouse model of LPS-induced cytokine release. Mice were pre-treated orally with vehicle or R835 prior to challenge with LPS and serum cytokine levels were monitored over a 24-hour period.Results:We have identified R835, a selective small molecule inhibitor of IRAK1 and IRAK4. R835 blocked LPS/TLR4 signaling and the resulting production of proinflammatory cytokines in both human and mouse cells and whole blood. R835 suppressed serum cytokine elevation in mice challenged with LPS.Conclusion:Our study demonstrates that R835, through inhibition of IRAK1/4 kinase activity, blocks LPS-induced cytokine production in vitro and in vivo. In a recent phase 1 study, R835 substantially reduced the increase of serum cytokines after an intravenous LPS challenge in healthy volunteers. Importantly, this shows that the pharmacological inhibition of IRAK1/4 pathway by R835 in humans mirrors the results obtained in mice. To our knowledge, R835 is the first dual IRAK1/4 inhibitor to enter clinical development and demonstrate inhibition of TLR4-induced cytokines in both mice and humans. R835 is a promising clinical candidate that will allow the exploration of IRAK1/4 inhibition in the treatment of cytokine-driven rheumatic and autoimmune diseases.References:[1]The interleukin-1 receptor/ Toll-like receptor superfamily: 10 years of progress. Luke A. J. O’Neill. Immunological Reviews 2008. Vol. 226: 10–18[2]Flannery S, Bowie A G. The interleukin-1 receptor-associated kinases: Critical regulators of innate immune signaling. Biochemical Pharmacology, Volume 80, Issue 12, 15 December 2010, Pages 1981-1991.Disclosure of Interests:Chrystelle Lamagna Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Caroline Gundel Shareholder of: Shareholder of Rigel Pharmaceuticals, Employee of: Employee of Rigel Pharmaceuticals, Meagan Chan Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Chi Young Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Sylvia Braselmann Shareholder of: Shareholder of Rigel Pharmaceuticals, Employee of: Employee of Rigel Pharmaceuticals, Roy Frances Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Sothy Yi Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Yan Chen Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Gary Park Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Lu Chou Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Esteban Masuda Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Vanessa Taylor Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals

Cytokine production by whole blood cells of the reconvalescents of community-acquired pneumonia under the influence of low-intensity microwave irradiation

10.12737/5025 ◽  
2014 ◽  
Vol 8 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Никифоров ◽  
V. Nikiforov ◽  
Терехов ◽  
I. Terekhov ◽  
Хадарцев ◽  
...  
Keyword(s):  
Microwave Radiation ◽  
Whole Blood ◽  
Blood Cells ◽  
Cytokine Production ◽  
Cell Activity ◽  
Community Acquired Pneumonia ◽  
Tnf Alpha ◽  
Toll Like Receptor ◽  
Low Intensity ◽  
Whole Blood Cells

The study discusses the effect on the functional state of the whole blood cells of low-intensity microwave radiation. On the model of intercellular interactions in the conditions of spontaneous cell activity and by stimulating cells complex mitogen, the influence of microwave radiation 1000 MHz on production by whole blood cells interleukins: IL-1β, 2, 6, 8, 10, 12, 13, 17A, TNF-alpha, IFN-g, RAIL-1, and soluble forms of toll-like receptor 1, 2, 4, 6 types was studied. The research results show that a single 45 minutes of exposure of microwave radiation of 0.05 PPM microwatt/cm2 has the ability to enhance mitogen-stimulated production of RAIL-1 by 38,7% (p=0.03), to reduce the induced production of IL-1β by 26,3% (p=0,037), IL-8 by 56,2% (p=0.022) and to increase oppressed segment complex mitogen production of IL-10 by 27,8% (p=0,041). The microwave radiation increased spontaneous and mitogen-stimulated expression of TLR, especially TLR1 during the initial low level.

scholarly journals Common Interaction Surfaces of the Toll-Like Receptor 4 Cytoplasmic Domain Stimulate Multiple Nuclear Targets

2003 ◽  
Vol 23 (7) ◽  
pp. 2543-2555 ◽  
Author(s):  
Tapani Ronni ◽  
Vishal Agarwal ◽  
Michael Haykinson ◽  
Margaret E. Haberland ◽  
Genhong Cheng ◽  
...  
Keyword(s):  
Target Genes ◽  
Interleukin 1 ◽  
Adaptor Proteins ◽  
Critical Surface ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Tlr4 Signaling ◽  
Tir Domain ◽  
Anti Inflammatory ◽  
Mutant Phenotypes

ABSTRACT Toll-like receptor 4 (TLR4) mediates the host response to lipopolysaccharide (LPS) by promoting the activation of pro- and anti-inflammatory cytokine genes. To activate each gene, numerous signal transduction pathways are required. The adaptor proteins MyD88 and TIRAP contribute to the activation of several and possibly all pathways via direct interactions with TLR4's Toll/interleukin-1 receptor (IL-1R) (TIR) domain. However, additional adaptors that are required for the activation of specific subsets of pathways may exist, which could contribute to the differential regulation of target genes. Furthermore, it remains unknown whether direct interactions that have been reported between TIR domains and other proteins are required for TLR4 signaling. To address these issues, we systematically mutated the TLR4 TIR domain in the context of a CD4/TLR4 fusion protein. Several exposed residues defining at least two structural surfaces were required in macrophages for activation of the proinflammatory IL-12 p40 and anti-inflammatory IL-10 promoters, as well as promoters dependent on individual transcription factors. Interestingly, the same residues were required by all promoters tested, suggesting that the signaling pathways diverge downstream of the adaptors. The mutant phenotypes provide a framework for future studies of TLR4 signaling, as the interaction supported by each critical surface residue will need to be defined.

scholarly journals Cell Activation by Ligands of the Toll-Like Receptor and Interleukin-1 Receptor Family Depends on the Function of the Large-Conductance Potassium Channel MaxiK in Human Macrophages

2006 ◽  
Vol 74 (7) ◽  
pp. 4354-4356 ◽  
Author(s):  
Olaf Scheel ◽  
Martin Papavlassopoulos ◽  
Rikard Blunck ◽  
Andreas Gebert ◽  
Thomas Hartung ◽  
...  
Keyword(s):  
Patch Clamp ◽  
Potassium Channel ◽  
Cell Activation ◽  
Cytokine Production ◽  
Interleukin 1 ◽  
Toll Like Receptor ◽  
Tlr Signaling ◽  
Human Macrophages ◽  
Maxik Channel ◽  
Receptor Family

ABSTRACT Performing patch-clamp experiments on human macrophages, we show that the K+ channel MaxiK is activated by lipopolysaccharide, peptidoglycan, and interleukin-1. Cytokine production initiated by several Toll-like receptor (TLR) ligands and by interleukin-1 is inhibited by MaxiK blockade. This provides evidence for functional association of the MaxiK channel and TLR signaling complexes.

scholarly journals Flagellin A Toll-Like Receptor 5 Agonist as an Adjuvant in Chicken Vaccines

2014 ◽  
Vol 21 (3) ◽  
pp. 261-270 ◽  
Author(s):  
Shishir Kumar Gupta ◽  
Preety Bajwa ◽  
Rajib Deb ◽  
Madhan Mohan Chellappa ◽  
Sohini Dey
Keyword(s):  
Infectious Diseases ◽  
Immune Cells ◽  
Cytokine Production ◽  
Innate Immune ◽  
Innate Immune Cells ◽  
Vaccine Adjuvants ◽  
Toll Like Receptor ◽  
Absolute Requirement ◽  
Toll Like Receptor 5 ◽  
Potential Use

ABSTRACTChicken raised under commercial conditions are vulnerable to environmental exposure to a number of pathogens. Therefore, regular vaccination of the flock is an absolute requirement to prevent the occurrence of infectious diseases. To combat infectious diseases, vaccines require inclusion of effective adjuvants that promote enhanced protection and do not cause any undesired adverse reaction when administered to birds along with the vaccine. With this perspective in mind, there is an increased need for effective better vaccine adjuvants. Efforts are being made to enhance vaccine efficacy by the use of suitable adjuvants, particularly Toll-like receptor (TLR)-based adjuvants. TLRs are among the types of pattern recognition receptors (PRRs) that recognize conserved pathogen molecules. A number of studies have documented the effectiveness of flagellin as an adjuvant as well as its ability to promote cytokine production by a range of innate immune cells. This minireview summarizes our current understanding of flagellin action, its role in inducing cytokine response in chicken cells, and the potential use of flagellin as well as its combination with other TLR ligands as an adjuvant in chicken vaccines.

scholarly journals Toll-Like Receptor 6 Plays an Important Role in Host Innate Resistance to Brucella abortus Infection in Mice

2013 ◽  
Vol 81 (5) ◽  
pp. 1654-1662 ◽  
Author(s):  
Leonardo A. de Almeida ◽  
Gilson C. Macedo ◽  
Fábio A. V. Marinho ◽  
Marco T. R. Gomes ◽  
Patrícia P. Corsetti ◽  
...  
Keyword(s):  
Immune Response ◽  
Dendritic Cells ◽  
Brucella Abortus ◽  
Proinflammatory Cytokine ◽  
Cytokine Production ◽  
Innate Immune ◽  
Proinflammatory Cytokine Production ◽  
Toll Like Receptor ◽  
Content Type

ABSTRACTBrucella abortusis recognized by several Toll-like receptor (TLR)-associated pathways triggering proinflammatory responses that affect both the nature and intensity of the immune response. Previously, we demonstrated thatB. abortus-mediated dendritic cell (DC) maturation and control of infection are dependent on the adaptor molecule MyD88. However, the involvement of all TLRs in response toB. abortusinfection is not completely understood. Therefore, we decided to evaluate the requirement for TLR6 in host resistance toB. abortus. Here, we demonstrated that TLR6 is an important component for triggering an innate immune response againstB. abortus. Anin vitroluciferase assay indicated that TLR6 cooperates with TLR2 to senseBrucellaand further activates NF-κB signaling. However,in vivoanalysis showed that TLR6, not TLR2, is required for the efficient control ofB. abortusinfection. Additionally,B. abortus-infected dendritic cells require TLR6 to induce tumor necrosis factor alpha (TNF-α) and interleukin-12 (IL-12). Furthermore, our findings demonstrated that the mitogen-activated protein kinase (MAPK) signaling pathway is impaired in TLR2, TLR6, and TLR2/6 knockout (KO) DCs when infected withB. abortus, which may account for the lower proinflammatory cytokine production observed in TLR6 KO mouse dendritic cells. In summary, the results presented here indicate that TLR6 is required to trigger innate immune responses againstB. abortusin vivoand is required for the full activation of DCs to induce robust proinflammatory cytokine production.

Interactions between Viperin, IRAK1 andTRAF6 couple innate immune signaling to antiviral ribonucleotide synthesis

2018 ◽  
Author(s):  
Arti B. Dumbrepatil ◽  
Soumi Ghosh ◽  
Ayesha M. Patel ◽  
Kelcie A. Zegalia ◽  
Paige A. Malec ◽  
...  
Keyword(s):  
Structural Changes ◽  
Interleukin 1 ◽  
Innate Immune ◽  
Tnf Receptor ◽  
Toll Like Receptor ◽  
Immune Signaling ◽  
Innate Immune Signaling ◽  
Synergistic Activation ◽  
Catalytically Active ◽  
Cellular Antiviral Response

SummaryViperin is a radical S-adenosylmethionine (SAM) enzyme that plays a multifaceted role in the cellular antiviral response. Viperin was recently shown to catalyze the SAM-dependent formation of 3′-deoxy-3′,4′-didehydro-CTP (ddhCTP), which inhibits some viral RNA polymerases. Viperin is also implicated in regulating K63-linked poly-ubiquitination of interleukin-1 receptor-associated kinase-1 (IRAK1) by the E3 ubiquitin ligase TNF Receptor-Associated Factor 6 (TRAF6) as part of the Toll-like receptor-7 and 9 (TLR7/9) innate immune signaling pathways. We show that IRAK1 and TRAF6 activate viperin to efficiently catalyze the radical-mediated dehydration of CTP to ddhCTP. Furthermore, poly-ubiquitination of IRAK1 requires the association of viperin with IRAK1 and TRAF6. Poly-ubiquitination appears dependent on structural changes induced by SAM binding to viperin but does not require catalytically active viperin. The synergistic activation of viperin and IRAK1 provides a mechanism that couples innate immune signaling with the production of the antiviral nucleotide ddhCTP.

SBT6050, a HER2-directed TLR8 therapeutic, as a systemically administered, tumor-targeted human myeloid cell agonist.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 3110-3110
Author(s):  
Heather Metz ◽  
Monica Childs ◽  
Jamie Brevik ◽  
Damion Winship ◽  
Ty Brender ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Cytokine Production ◽  
Single Agent ◽  
Myeloid Cells ◽  
Myeloid Cell ◽  
Clinical Development ◽  
Innate Immune ◽  
Mouse Tumor ◽  
Systemic Delivery ◽  
Mouse Tumor Models

3110 Background: Solid tumors are replete with myeloid cells which, when activated, drive potent anti-tumor responses. Clinical development of systemically administered myeloid cell agonists, however, has been hindered by acute toxicities due to peripheral activation of the targeted cell types. Intratumoral administration, the route of delivery typically used for innate immune/myeloid cell agonists, is limited by tumor accessibility and a dependence on abscopal responses. A systemically delivered myeloid cell agonist with tumor-localized activity has the potential to overcome challenges encountered with other innate immune/myeloid cell agonists in clinical development. Methods: SBT6050 is a novel therapeutic comprised of a potent toll-like receptor (TLR) 8 agonist payload conjugated to a HER2-directed monoclonal antibody. Delivery of the payload into the endosome of human myeloid cells, where TLR8 resides, requires the co-engagement of HER2 on tumor cells and Fc gamma receptor on human myeloid cells. Thus, SBT6050 is designed for systemic delivery and tumor-targeted activation of human myeloid cells. Results: Studies with human immune cells show that SBT6050 potently induces, in a HER2-dependent manner, multiple anti-tumor immune activities due to its direct activation of myeloid cells and the subsequent induction of T and NK cell cytolytic activity. SBT6050 is designed to activate human myeloid cells only in the presence of HER2-positive tumor cells with moderate (2+ by IHC) or high (3+ by IHC) expression levels. Tumor-localized activity has been demonstrated in mouse models using a SBT6050 mouse surrogate. Systemic delivery results in robust single agent efficacy in multiple mouse tumor models, even those engineered to lack T cells, without accompanying peripheral cytokine production. Trastuzumab and SBT6050 bind to distinct epitopes on HER2 and enhanced activity is observed when the two agents are combined. Conclusions: SBT6050 is a systemically administered, tumor-targeted myeloid cell agonist that demonstrates single agent efficacy in multiple mouse tumor models without peripheral cytokine production. A first-in-human study with SBT6050 is expected to begin this year for patients with HER2-expressing solid tumors.

scholarly journals Toll-like Receptors Induce a Phagocytic Gene Program through p38

2003 ◽  
Vol 199 (1) ◽  
pp. 81-90 ◽  
Author(s):  
Sean E. Doyle ◽  
Ryan M. O'Connell ◽  
Gustavo A. Miranda ◽  
Sagar A. Vaidya ◽  
Edward K. Chow ◽  
...  
Keyword(s):  
Immune Responses ◽  
Interleukin 1 ◽  
Innate Immune ◽  
Myeloid Differentiation ◽  
Innate Immune Responses ◽  
Toll Like Receptor ◽  
Evolutionarily Conserved ◽  
Myeloid Differentiation Factor ◽  
The Relationship ◽  
Number Of Bacteria

Toll-like receptor (TLR) signaling and phagocytosis are hallmarks of macrophage-mediated innate immune responses to bacterial infection. However, the relationship between these two processes is not well established. Our data indicate that TLR ligands specifically promote bacterial phagocytosis, in both murine and human cells, through induction of a phagocytic gene program. Importantly, TLR-induced phagocytosis of bacteria was found to be reliant on myeloid differentiation factor 88–dependent signaling through interleukin-1 receptor–associated kinase-4 and p38 leading to the up-regulation of scavenger receptors. Interestingly, individual TLRs promote phagocytosis to varying degrees with TLR9 being the strongest and TLR3 being the weakest inducer of this process. We also demonstrate that TLR ligands not only amplify the percentage of phagocytes uptaking Escherichia coli, but also increase the number of bacteria phagocytosed by individual macrophages. Taken together, our data describe an evolutionarily conserved mechanism by which TLRs can specifically promote phagocytic clearance of bacteria during infection.

scholarly journals Toll-like receptor 9 mediates innate immune activation by the malaria pigment hemozoin

2005 ◽  
Vol 201 (1) ◽  
pp. 19-25 ◽  
Author(s):  
Cevayir Coban ◽  
Ken J. Ishii ◽  
Taro Kawai ◽  
Hiroaki Hemmi ◽  
Shintaro Sato ◽  
...  
Keyword(s):  
Immune Responses ◽  
Immune Activation ◽  
Interleukin 1 ◽  
Innate Immune ◽  
Dependent Manner ◽  
Innate Immune Responses ◽  
Toll Like Receptor ◽  
Innate Immune Activation

Malaria parasites within red blood cells digest host hemoglobin into a hydrophobic heme polymer, known as hemozoin (HZ), which is subsequently released into the blood stream and then captured by and concentrated in the reticulo-endothelial system. Accumulating evidence suggests that HZ is immunologically active, but the molecular mechanism(s) through which HZ modulates the innate immune system has not been elucidated. This work demonstrates that HZ purified from Plasmodium falciparum is a novel non-DNA ligand for Toll-like receptor (TLR)9. HZ activated innate immune responses in vivo and in vitro, resulting in the production of cytokines, chemokines, and up-regulation of costimulatory molecules. Such responses were severely impaired in TLR9−/− and myeloid differentiation factor 88 (MyD88)−/−, but not in TLR2, TLR4, TLR7, or Toll/interleukin 1 receptor domain–containing adaptor-inducing interferon β−/− mice. Synthetic HZ, which is free of the other contaminants, also activated innate immune responses in vivo in a TLR9-dependent manner. Chloroquine (CQ), an antimalarial drug, abrogated HZ-induced cytokine production. These data suggest that TLR9-mediated, MyD88-dependent, and CQ-sensitive innate immune activation by HZ may play an important role in malaria parasite–host interactions.

scholarly journals DNA Sensing in the Innate Immune Response

Physiology ◽  
2020 ◽  
Vol 35 (2) ◽  
pp. 112-124 ◽  
Author(s):  
Benoit Briard ◽  
David E. Place ◽  
Thirumala-Devi Kanneganti
Keyword(s):  
Immune Responses ◽  
Cytokine Production ◽  
Rna Polymerase Iii ◽  
Innate Immune ◽  
Toll Like Receptor ◽  
Dna Sensing ◽  
Dead Box ◽  
A Cell ◽  
Cell Cytosol ◽  
Molecular Patterns

The innate immune system recognizes conserved pathogen-associated molecular patterns and produces inflammatory cytokines that direct downstream immune responses. The inappropriate localization of DNA within the cell cytosol or endosomal compartments indicates that a cell may either be infected by a DNA virus or bacterium, or has problems with its own nuclear integrity. This DNA is sensed by certain receptors that mediate cytokine production and, in some cases, initiate an inflammatory and lytic form of cell death called pyroptosis. Dysregulation of these DNA-sensing pathways is thought to contribute to autoimmune diseases and the development of cancer. In this review, we will discuss the DNA sensors Toll-like receptor 9 (TLR9), cyclic GMP-AMP synthase (cGAS), stimulator of interferon genes (STING), absent in melanoma 2 (AIM2), and interferon gamma-inducible 16 (IFI16), their ligands, and their physiological significance. We will also examine the less-well-understood DEAH- and DEAD-box helicases DHX9, DHX36, DDX41, and RNA polymerase III, each of which may play an important role in DNA-mediated innate immunity.

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