scholarly journals TICAM-1/TRIF associates with Act1 and suppresses IL-17 receptor–mediated inflammatory responses

2021 ◽  
Vol 5 (2) ◽  
pp. e202101181
Author(s):  
Yusuke Miyashita ◽  
Takahisa Kouwaki ◽  
Hirotake Tsukamoto ◽  
Masaaki Okamoto ◽  
Kimitoshi Nakamura ◽  
...  
Keyword(s):  
Map Kinases ◽  
Inflammatory Responses ◽  
Lymphoid Cells ◽  
Negative Regulator ◽  
Delayed Type Hypersensitivity ◽  
Autoimmune Encephalomyelitis ◽  
Cytokines And Chemokines ◽  
Enhanced Expression ◽  
Tlr3 Signaling

TICAM-1 (also called TRIF) is the sole adaptor of TLR3 that recognizes double-stranded RNA. Here, we report that TICAM-1 is involved not only in TLR3 signaling but also in the cytokine receptor IL-17RA signaling. We found that TICAM-1 bound to IL-17R adaptor Act1 to inhibit the interaction between IL-17RA and Act1. Interestingly, TICAM-1 knockout promoted IL-17RA/Act1 interaction and increased IL-17A–mediated activation of NF-κB and MAP kinases, leading to enhanced expression of inflammatory cytokines and chemokines upon IL-17A stimulation. Moreover, Ticam-1 knockout augmented IL-17A–mediated CXCL1 and CXCL2 expression in vivo, resulting in accumulation of myeloid cells. Furthermore, Ticam-1 knockout enhanced delayed type hypersensitivity and exacerbated experimental autoimmune encephalomyelitis. Ticam-1 knockout promoted accumulation of myeloid and lymphoid cells in the spinal cord of EAE-induced mice. Collectively, these data indicate that TICAM-1 inhibits the interaction between IL-17RA and Act1 and functions as a negative regulator in IL-17A–mediated inflammatory responses.

scholarly journals Modulation of experimental autoimmune encephalomyelitis through TRAF3-mediated suppression of interleukin 17 receptor signaling

2010 ◽  
Vol 207 (12) ◽  
pp. 2647-2662 ◽  
Author(s):  
Shu Zhu ◽  
Wen Pan ◽  
Peiqing Shi ◽  
Hanchao Gao ◽  
Fang Zhao ◽  
...  
Keyword(s):  
Experimental Autoimmune Encephalomyelitis ◽  
Inflammatory Cytokine ◽  
Inflammatory Responses ◽  
Negative Regulator ◽  
Mitogen Activated Protein Kinase ◽  
Interleukin 17 ◽  
Receptor Signaling ◽  
Autoimmune Encephalomyelitis ◽  
Experimental Autoimmune

Interleukin 17 (IL-17) plays critical roles in the pathogenesis of various autoimmune diseases, including experimental autoimmune encephalomyelitis (EAE). How the signals triggered by this powerful inflammatory cytokine are controlled to avoid abnormal inflammatory responses is not well understood. In this study, we report that TRAF3 is a receptor proximal negative regulator of IL-17 receptor (IL-17R) signaling. TRAF3 greatly suppressed IL-17–induced NF-κB and mitogen-activated protein kinase activation and subsequent production of inflammatory cytokines and chemokines. Mechanistically, the binding of TRAF3 to IL-17R interfered with the formation of the receptor signaling activation complex IL-17R–Act1–TRAF6, resulting in suppression of downstream signaling. TRAF3 markedly inhibited IL-17–induced expression of inflammatory cytokine and chemokine genes in vivo and consequently delayed the onset and greatly reduced the incidence and severity of EAE. Thus, TRAF3 is a negative regulator of IL-17R proximal signaling.

Inhibition of monocyte-derived inflammatory cytokines by IL-25 occurs via p38 Map kinase–dependent induction of Socs-3

Blood ◽  
2009 ◽  
Vol 113 (15) ◽  
pp. 3512-3519 ◽  
Author(s):  
Roberta Caruso ◽  
Carmine Stolfi ◽  
Massimiliano Sarra ◽  
Angelamaria Rizzo ◽  
Massimo C. Fantini ◽  
...  
Keyword(s):  
Map Kinase ◽  
Inflammatory Cytokines ◽  
Inflammatory Responses ◽  
Human Peripheral Blood ◽  
Serum Levels ◽  
Cell Types ◽  
P38 Map Kinase ◽  
Negative Regulator ◽  
Therapeutic Implications

Abstract IL-25, a member of the IL-17 cytokine family, is known to enhance Th2-like responses associated with increased serum levels of IgE, IgG1, IgA, blood eosinophilia, and eosinophilic infiltrates in various tissues. However, IL-25 also abrogates inflammatory responses driven by Th17 cells. However, the cell types that respond to IL-25 and the mechanisms by which IL-25 differentially regulates immune reactions are not well explored. To identify potential targets of IL-25, we initially examined IL-25 receptor (IL-25R) in human peripheral blood cells. IL-25R was predominantly expressed by CD14+ cells. We next assessed the functional role of IL-25 in modulating the response of CD14+ cells to various inflammatory signals. CD14+ cells responded to IL-25 by down-regulating the synthesis of inflammatory cytokines induced by toll-like receptor (TLR) ligands and inflammatory cytokines. Inhibition of cytokine response by IL-25 occurred via a p38 Map kinase–driven Socs-3–dependent mechanism. In vivo, IL-25 inhibited monocyte-derived cytokines and protected against LPS-induced lethal endotoxemia in mice. These data indicate that IL-25 is a negative regulator of monocyte proinflammatory cytokine responses, which may have therapeutic implications.

Silencing of junctional adhesion molecule-like protein attenuates atherogenesis and enhances plaque stability in ApoE−/− mice

2019 ◽  
Vol 133 (11) ◽  
pp. 1215-1228 ◽  
Author(s):  
Yu Sun ◽  
Juan Guan ◽  
Yunfeng Hou ◽  
Fei Xue ◽  
Wei Huang ◽  
...  
Keyword(s):  
Adhesion Molecule ◽  
Wound Repair ◽  
Inflammatory Responses ◽  
Atherosclerotic Lesion ◽  
Atherosclerotic Plaques ◽  
Plaque Stability ◽  
Fibrous Cap ◽  
Enhanced Expression

Abstract Background: Although junctional adhesion molecule-like protein (JAML) has recently been implicated in leukocyte recruitment during inflammation and wound repair, its role in atherosclerosis remains to be elucidated. Methods and results: First, we showed that JAML was strongly expressed in atherosclerotic plaques of cardiovascular patients. Similar results were obtained with atherosclerotic plaques of ApoE−/− mice. Co-immunofluorescence staining showed that JAML was mainly expressed in macrophages. Enhanced expression of JAML in cultured macrophages was observed following exposure of the cells to oxLDL. The functional role of JAML in atherosclerosis and macrophages function was assessed by interference of JAML with shRNA in vivo and siRNA in vitro. Silencing of JAML in mice significantly attenuated atherosclerotic lesion formation, reduced necrotic core area, increased plaque fibrous cap thickness, decreased macrophages content and inflammation. In addition, histological staining showed that JAML deficiency promoted plaques to stable phenotype. In vitro, JAML siRNA treatment lowered the expression of inflammatory cytokines in macrophages treated with oxLDL. The mechanism by which JAML mediated the inflammatory responses may be related to the ERK/NF-κB activation. Conclusions: Our results demonstrated that therapeutic drugs which antagonize the function of JAML may be a potentially effective approach to attenuate atherogenesis and enhance plaque stability.

Thymic Immunosuppressive Pentapeptide (TIPP) Showed Anticancer Activity in Breast Cancer and Chronic Myeloid Leukemia Both In Vitro and In Vivo

2021 ◽  
Vol 28 ◽  
Author(s):  
Muhammad Ijaz ◽  
Muhammad Shahbaz ◽  
Wenjie Jiang ◽  
Yikang Shi ◽  
Xiuli Guo ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Chronic Myeloid Leukemia ◽  
Anticancer Activity ◽  
Myeloid Leukemia ◽  
Map Kinases ◽  
Inflammatory Responses ◽  
Tumor Xenograft ◽  
Immunohistochemistry Analysis

Aim: Being the common cause and major burden of deaths globally, timely management of cancer is crucial. Background: Thymic immunosuppressive pentapeptide (TIPP) is a novel pentapeptide originally obtained from calf thymic immunosuppressive extract. Previously, TIPP has been proved to suppress the allergic and inflammatory responses in allergic mice via blocking MAP kinases/NF-κB signaling pathways. Objective: In this study, in vitro anticancer activity of TIPP was tested on two different types of cancers using MCF-7 and K562 cell lines. Methods: Tumor xenograft models for breast cancer and chronic myeloid leukemia were designed. In vivo anticancer activity of TIPP was investigated on both cancer types. The liver and tumor tissues of the mice were preserved for immunohistochemistry analysis. Results: In vitro anticancer activity of TIPP showed significant inhibition on cell viability of both breast cancer and chronic myeloid leukemia. In vivo anticancer effect of TIPP in both types of cancer models further proved the potent anticancer nature of TIPP. Immunohistochemistry analysis assured that TIPP is a safe drug for normal organs such as the liver. Conclusion: Our present study revealed that TIPP is a potent anticancer drug and an important treatment option for various diseases. Further work is needed to test the flexible and proficient activity of the novel peptide.

scholarly journals CTLA-4: a negative regulator of autoimmune disease.

1996 ◽  
Vol 184 (2) ◽  
pp. 783-788 ◽  
Author(s):  
N J Karandikar ◽  
C L Vanderlugt ◽  
T L Walunas ◽  
S D Miller ◽  
J A Bluestone
Keyword(s):  
T Cells ◽  
Autoimmune Disease ◽  
Demyelinating Disease ◽  
Negative Regulator ◽  
Autoimmune Encephalomyelitis ◽  
Activated T Cells ◽  
In Vitro Proliferation ◽  
Lymph Node Cells

CTLA-4, a CD28 homologue expressed on activated T cells, binds with high affinity to the CD28 ligands, B7-1 (CD80) and B7-2 (CD86). This study was designed to examine the role of CTLA-4 in regulating autoimmune disease. Murine relapsing-remitting experimental autoimmune encephalomyelitis (R-EAE) is a demyelinating disease mediated by PLP139-151-specific CD4+ T cells in SJL/J mice. Anti-CTLA-4 mAbs (or their F(ab) fragments) enhanced in vitro proliferation and pro-inflammatory cytokine production by PLP139-151-primed lymph node cells. Addition of either reagent to in vitro activation cultures potentiated the ability of T cells to adoptively transfer disease to naive recipients. In vivo administration of anti-CTLA-4 mAb to recipients of PLP139-151-specific T cells resulted in accelerated and exacerbated disease. Finally, anti-CTLA-4 treatment of mice during disease remission resulted in the exacerbation of relapses. Collectively, these results suggest that CTLA-4 mediates the downregulation of ongoing immune responses and plays a major role in regulating autoimmunity.

scholarly journals Mycoplasma pneumoniae-Derived Lipopeptides Induce Acute Inflammatory Responses in the Lungs of Mice

2007 ◽  
Vol 76 (1) ◽  
pp. 270-277 ◽  
Author(s):  
Takashi Shimizu ◽  
Yutaka Kida ◽  
Koichi Kuwano
Keyword(s):  
Mycoplasma Pneumoniae ◽  
Inflammatory Responses ◽  
Lavage Fluid ◽  
Peritoneal Macrophages ◽  
Necrosis Factor Alpha ◽  
Chemokine Production ◽  
Cytokines And Chemokines ◽  
Tnf Α ◽  
Mouse Peritoneal Macrophages

ABSTRACT The pathogenesis of Mycoplasma pneumoniae infection is considered to be in part attributable to excessive immune responses. In this study, we investigated whether synthetic lipopeptides of subunit b of F0F1-type ATPase (F0F1-ATPase), NF-κB-activating lipoprotein 1 (N-ALP1), and N-ALP2 (named FAM20, sN-ALP1, and sN-ALP2, respectively) derived from M. pneumoniae induce cytokine and chemokine production and leukocyte infiltration in vivo. Intranasal administration of FAM20 and sN-ALP2 induced infiltration of leukocyte cells and production of chemokines and cytokines in bronchoalveolar lavage fluid, but sN-ALP1 failed to do so. The activity of FAM20 was notably higher than that of sN-ALP2. FAM20 and sN-ALP2 induced tumor necrosis factor alpha (TNF-α) through Toll-like receptor 2 in mouse peritoneal macrophages. Moreover, in the range of low concentrations of lipopeptides, FAM20 showed relatively high activity of inducing TNF-α in mouse peritoneal macrophages compared to synthetic lipopeptides such as MALP-2 and FSL-1, derived from Mycoplasma fermentans and Mycoplasma salivarium, respectively. These findings indicate that the F0F1-ATPase might be a key molecule in inducing cytokines and chemokines contributing to inflammatory responses during M. pneumoniae infection in vivo.

scholarly journals Immune checkpoints on innate lymphoid cells

2017 ◽  
Vol 214 (6) ◽  
pp. 1561-1563 ◽  
Author(s):  
Laura Chiossone ◽  
Eric Vivier
Keyword(s):  
Cytokine Production ◽  
Innate Lymphoid Cells ◽  
Lymphoid Cells ◽  
Negative Regulator ◽  
Immune Checkpoints ◽  
Group 2 ◽  
Blocking Antibodies

In this issue of JEM, Taylor et al. (https://doi.org/10.1084/jem.20161653) describe PD-1 as a critical negative regulator of group 2 innate lymphoid cells (ILC-2s). PD-1 intrinsically controls proliferation and cytokine production of both mouse and human ILC-2s. PD-1 signaling inhibits STAT5 phosphorylation and the removal of this brake by knocking down PD-1 expression or by using anti–PD-1 blocking antibodies, translated in vivo into better clearance of helminth worm infection in mice.

scholarly journals Treatment of inflammatory arthritis via targeting of tristetraprolin, a master regulator of pro-inflammatory gene expression

2016 ◽  
Vol 76 (3) ◽  
pp. 612-619 ◽  
Author(s):  
E A Ross ◽  
A J Naylor ◽  
J D O'Neil ◽  
T Crowley ◽  
M L Ridley ◽  
...  
Keyword(s):  
Inflammatory Arthritis ◽  
Inflammatory Responses ◽  
Vascular Endothelial Cells ◽  
Bone Erosion ◽  
Negative Regulator ◽  
Mitogen Activated Protein Kinase ◽  
Critical Determinant ◽  
Anti Inflammatory

ObjectivesTristetraprolin (TTP), a negative regulator of many pro-inflammatory genes, is strongly expressed in rheumatoid synovial cells. The mitogen-activated protein kinase (MAPK) p38 pathway mediates the inactivation of TTP via phosphorylation of two serine residues. We wished to test the hypothesis that these phosphorylations contribute to the development of inflammatory arthritis, and that, conversely, joint inflammation may be inhibited by promoting the dephosphorylation and activation of TTP.MethodsThe expression of TTP and its relationship with MAPK p38 activity were examined in non-inflamed and rheumatoid arthritis (RA) synovial tissue. Experimental arthritis was induced in a genetically modified mouse strain, in which endogenous TTP cannot be phosphorylated and inactivated. In vitro and in vivo experiments were performed to test anti-inflammatory effects of compounds that activate the protein phosphatase 2A (PP2A) and promote dephosphorylation of TTP.ResultsTTP expression was significantly higher in RA than non-inflamed synovium, detected in macrophages, vascular endothelial cells and some fibroblasts and co-localised with MAPK p38 activation. Substitution of TTP phosphorylation sites conferred dramatic protection against inflammatory arthritis in mice. Two distinct PP2A agonists also reduced inflammation and prevented bone erosion. In vitro anti-inflammatory effects of PP2A agonism were mediated by TTP activation.ConclusionsThe phosphorylation state of TTP is a critical determinant of inflammatory responses, and a tractable target for novel anti-inflammatory treatments.

scholarly journals Tle1 tumor suppressor negatively regulates inflammation in vivo and modulates NF-κB inflammatory pathway

2016 ◽  
Vol 113 (7) ◽  
pp. 1871-1876 ◽  
Author(s):  
Selvi Ramasamy ◽  
Borja Saez ◽  
Subhankar Mukhopadhyay ◽  
Daching Ding ◽  
Alwiya M. Ahmed ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Cancer Progression ◽  
Inflammatory Diseases ◽  
Negative Regulator ◽  
Lung Hypoplasia ◽  
Cellular Functions ◽  
Cytokines And Chemokines ◽  
Inflammatory Phenotype ◽  
Enhancer Of Split

Tle1 (transducin-like enhancer of split 1) is a corepressor that interacts with a variety of DNA-binding transcription factors and has been implicated in many cellular functions; however, physiological studies are limited. Tle1-deficient (Tle1Δ/Δ) mice, although grossly normal at birth, exhibit skin defects, lung hypoplasia, severe runting, poor body condition, and early mortality. Tle1Δ/Δ mice display a chronic inflammatory phenotype with increased expression of inflammatory cytokines and chemokines in the skin, lung, and intestine and increased circulatory IL-6 and G-CSF, along with a hematopoietic shift toward granulocyte macrophage progenitor and myeloid cells. Tle1Δ/Δ macrophages produce increased inflammatory cytokines in response to Toll-like receptor (TLR) agonists and lipopolysaccharides (LPS), and Tle1Δ/Δ mice display an enhanced inflammatory response to ear skin 12-O-tetradecanoylphorbol-13-acetate treatment. Loss of Tle1 not only results in increased phosphorylation and activation of proinflammatory NF-κB but also results in decreased Hes1 (hairy and enhancer of split-1), a negative regulator of inflammation in macrophages. Furthermore, Tle1Δ/Δ mice exhibit accelerated growth of B6-F10 melanoma xenografts. Our work provides the first in vivo evidence, to our knowledge, that TLE1 is a major counterregulator of inflammation with potential roles in a variety of inflammatory diseases and in cancer progression.

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