scholarly journals Interleukin (Il)-18 Promotes the Development of Chronic Gastrointestinal Helminth Infection by Downregulating IL-13

2001 ◽  
Vol 194 (3) ◽  
pp. 355-364 ◽  
Author(s):  
Helena Helmby ◽  
Kiyoshi Takeda ◽  
Shizuo Akira ◽  
Richard K. Grencis
Keyword(s):  
Critical Role ◽  
Gastrointestinal Nematode ◽  
Inhibitory Effect ◽  
Trichuris Muris ◽  
Gastrointestinal Helminth ◽  
Th Cell ◽  
Ifn Γ ◽  
In Vivo Treatment ◽  
Deficient Mice

Expulsion of the gastrointestinal nematode Trichuris muris is mediated by a T helper (Th) 2 type response involving interleukin (IL)-4 and IL-13. Here we show that Th1 response–associated susceptibility involves prior activation of IL-18 and caspase-1 followed by IL-12 and interferon (IFN)-γ in the intestine. IL-18–deficient mice are highly resistant to chronic T. muris infection and in vivo treatment of normal mice with recombinant (r)IL-18 suppresses IL-13 and IL-4 secretion but does not affect IFN-γ. In vivo treatment of T. muris–infected IFN-γ–deficient mice with rIL-18 demonstrated that the inhibitory effect of IL-18 on IL-13 secretion is independent of IFN-γ. Hence, IL-18 does not function as an IFN-γ–inducing cytokine during chronic T. muris infection but rather as a direct regulator of Th2 cytokines. These results provide the first demonstration of the critical role of IL-18 in regulating Th cell responses during gastrointestinal nematode infection.

scholarly journals Muc5ac: a critical component mediating the rejection of enteric nematodes

2011 ◽  
Vol 208 (5) ◽  
pp. 893-900 ◽  
Author(s):  
Sumaira Z. Hasnain ◽  
Christopher M. Evans ◽  
Michelle Roy ◽  
Amanda L. Gallagher ◽  
Kristen N. Kindrachuk ◽  
...  
Keyword(s):  
De Novo ◽  
Trichinella Spiralis ◽  
Nematode Infection ◽  
Nippostrongylus Brasiliensis ◽  
Chronic Infections ◽  
Trichuris Muris ◽  
Intestinal Nematode ◽  
Ifn Γ ◽  
Deficient Mice

De novo expression of Muc5ac, a mucin not normally expressed in the intestinal tract, is induced in the cecum of mice resistant to Trichuris muris infection. In this study, we investigated the role of Muc5ac, which is detected shortly before worm expulsion and is associated with the production of interleukin-13 (IL-13), in resistance to this nematode. Muc5ac-deficient mice were incapable of expelling T. muris from the intestine and harbored long-term chronic infections, despite developing strong TH2 responses. Muc5ac-deficient mice had elevated levels of IL-13 and, surprisingly, an increase in the TH1 cytokine IFN-γ. Because TH1 inflammation is thought to favor chronic nematode infection, IFN-γ was neutralized in vivo, resulting in an even stronger TH2-type immune response. Nevertheless, despite a more robust TH2 effector response, the Muc5ac-deficient mice remained highly susceptible to chronic T. muris infection. Importantly, human MUC5AC had a direct detrimental effect on nematode vitality. Moreover, the absence of Muc5ac caused a significant delay in the expulsion of two other gut-dwelling nematodes (Trichinella spiralis and Nippostrongylus brasiliensis). Thus, for the first time, we identify a single mucin, Muc5ac, as a direct and critical mediator of resistance during intestinal nematode infection.

scholarly journals Inhibition of T Helper Cell Type 2 Cell Differentiation and Immunoglobulin E Response by Ligand-Activated Vα14 Natural Killer T Cells

1999 ◽  
Vol 190 (6) ◽  
pp. 783-792 ◽  
Author(s):  
Junqing Cui ◽  
Naohiro Watanabe ◽  
Tetsu Kawano ◽  
Masakatsu Yamashita ◽  
Tohru Kamata ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Natural Killer ◽  
Nkt Cells ◽  
Minor Effect ◽  
Th2 Cell ◽  
Th Cell ◽  
Ifn Γ ◽  
Deficient Mice ◽  
Natural Killer T

Murine Vα14 natural killer T (NKT) cells are thought to play a crucial role in various immune responses, including infectious, allergic, and autoimmune diseases. Because Vα14 NKT cells produce large amounts of both interleukin (IL)-4 and interferon (IFN)-γ upon in vivo stimulation with a specific ligand, α-galactosylceramide (α-GalCer), or after treatment with anti-CD3 antibody, a regulatory role on helper T (Th) cell differentiation has been proposed for these cells. However, the identity of the cytokine produced by Vα14 NKT cells that play a dominant role on the Th cell differentiation still remains controversial. Here, we demonstrate by using Vα14 NKT-deficient mice that Vα14 NKT cells are dispensable for the induction of antigen-specific immunoglobulin (Ig)E responses induced by ovalbumin immunization or Nippostrongylus brasiliensis infection. However, upon in vivo activation with α-GalCer, Vα14 NKT cells are found to suppress antigen-specific IgE production. The suppression appeared to be IgE specific, and was not detected in either Vα14 NKT– or IFN-γ–deficient mice. Consistent with these results, we also found that ligand-activated Vα14 NKT cells inhibited Th2 cell differentiation in an in vitro induction culture system. Thus, it is likely that activated Vα14 NKT cells exert a potent inhibitory effect on Th2 cell differentiation and subsequent IgE production by producing a large amount of IFN-γ. In marked contrast, our studies have revealed that IL-4 produced by Vα14 NKT cells has only a minor effect on Th2 cell differentiation.

scholarly journals Essential role of IPS-1 in innate immune responses against RNA viruses

2006 ◽  
Vol 203 (7) ◽  
pp. 1795-1803 ◽  
Author(s):  
Himanshu Kumar ◽  
Taro Kawai ◽  
Hiroki Kato ◽  
Shintaro Sato ◽  
Ken Takahashi ◽  
...  
Keyword(s):  
Rna Viruses ◽  
Rna Virus ◽  
Critical Role ◽  
Nuclear Factor Κb ◽  
Type I ◽  
Innate Immune Responses ◽  
Antiviral Responses ◽  
Deficient Mice

IFN-β promoter stimulator (IPS)-1 was recently identified as an adapter for retinoic acid–inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (Mda5), which recognize distinct RNA viruses. Here we show the critical role of IPS-1 in antiviral responses in vivo. IPS-1–deficient mice showed severe defects in both RIG-I– and Mda5-mediated induction of type I interferon and inflammatory cytokines and were susceptible to RNA virus infection. RNA virus–induced interferon regulatory factor-3 and nuclear factor κB activation was also impaired in IPS-1–deficient cells. IPS-1, however, was not essential for the responses to either DNA virus or double-stranded B-DNA. Thus, IPS-1 is the sole adapter in both RIG-I and Mda5 signaling that mediates effective responses against a variety of RNA viruses.

scholarly journals A Signal Transducer and Activator of  Transcription (Stat)4-independent Pathway for the Development of  T Helper Type 1 Cells

1998 ◽  
Vol 188 (6) ◽  
pp. 1191-1196 ◽  
Author(s):  
Mark H. Kaplan ◽  
Andrea L. Wurster ◽  
Michael J. Grusby
Keyword(s):  
Delayed Type Hypersensitivity ◽  
Th2 Cells ◽  
Signal Transducer ◽  
T Helper ◽  
Th1 Cell ◽  
Th Cells ◽  
Th Cell ◽  
Ifn Γ

The differentiation of T helper (Th) cells is regulated by members of the signal transducer and activator of transcription (STAT) family of signaling molecules. We have generated mice lacking both Stat4 and Stat6 to examine the ability of Th cells to develop in the absence of these two transcription factors. Stat4, Stat6−/− lymphocytes fail to differentiate into interleukin (IL)-4–secreting Th2 cells. However, in contrast to Stat4−/− lymphocytes, T cells from Stat4, Stat6−/− mice produce significant amounts of interferon (IFN)-γ when activated in vitro. Although Stat4, Stat6−/− lymphocytes produce less IFN-γ than IL-12–stimulated control lymphocytes, equivalent numbers of IFN-γ–secreting cells can be generated from cultures of Stat4, Stat6−/− lymphocytes activated under neutral conditions and control lymphocytes activated under Th1 cell–promoting conditions. Moreover, Stat4, Stat6−/− mice are able to mount an in vivo Th1 cell–mediated delayed-type hypersensitivity response. These results support a model of Th cell differentiation in which the generation of Th2 cells requires Stat6, whereas a Stat4-independent pathway exists for the development of Th1 cells.

scholarly journals Rapid G protein-regulated activation event involved in lymphocyte binding to high endothelial venules.

1993 ◽  
Vol 178 (1) ◽  
pp. 367-372 ◽  
Author(s):  
R F Bargatze ◽  
E C Butcher
Keyword(s):  
G Protein ◽  
Pertussis Toxin ◽  
Critical Role ◽  
Lymphocyte Activation ◽  
Inhibitory Effect ◽  
Peyer's Patches ◽  
Peyer’S Patches ◽  
High Endothelial Venules ◽  
Activation Event

The homing of blood borne lymphocytes into lymph nodes and Peyer's patches is mediated in part by recognition and binding to specialized high endothelial venules (HEV). Here we demonstrate that a rapid pertussis toxin-sensitive lymphocyte activation event can participate in lymphocyte recognition of HEV. In situ video microscopic analyses of lymphocyte interactions with HEV in exteriorized mouse Peyer's patches reveal that pertussis toxin has no effect on an initial "rolling" displayed by many lymphocytes, but inhibits an activation-dependent "sticking" event required for lymphocyte arrest. This is the first demonstration that physiologic lymphocyte-endothelial interactions can involve sequential rolling, activation, and activation-dependent arrest, previously shown only for neutrophils. The inhibitory effect of the toxin is dependent on its G protein-modifying ADP-ribosyltransferase activity and can be reversed by phorbol myristic acetate, which bypasses cell surface receptors to trigger activation-dependent adhesion. Lymphocyte sticking can occur within 1-3 s after initiation of rolling. We conclude that a rapid receptor-mediated activation event involving G protein signaling can trigger stable lymphocyte attachment to HEV in vivo, and may play a critical role in regulating lymphocyte homing.

Disruption of endothelial Pfkfb3 ameliorates diet-induced murine insulin resistance

2021 ◽  
Author(s):  
Qiuhua Yang ◽  
Jiean Xu ◽  
Qian Ma ◽  
Zhiping Liu ◽  
Yaqi Zhou ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Endothelial Cells ◽  
High Fat Diet ◽  
Inflammatory Responses ◽  
Critical Role ◽  
Endothelial Inflammation ◽  
Glucose Clearance ◽  
Deficient Mice

Overnutrition-induced endothelial inflammation plays a crucial role in high fat diet (HFD)-induced insulin resistance in animals. Endothelial glycolysis plays a critical role in endothelial inflammation and proliferation, but its role in diet-induced endothelial inflammation and subsequent insulin resistance has not been elucidated. PFKFB3 is a critical glycolytic regulator, and its increased expression has been observed in adipose vascular endothelium of C57BL/6J mice fed with HFD in vivo, and in palmitate (PA)-treated primary human adipose microvascular endothelial cells (HAMECs) in vitro. We generated mice with Pfkfb3 deficiency selective for endothelial cells to examine the effect of endothelial Pfkfb3 in endothelial inflammation in metabolic organs and in the development of HFD-induced insulin resistance. EC Pfkfb3-deficient mice exhibited mitigated HFD-induced insulin resistance, including decreased body weight and fat mass, improved glucose clearance and insulin sensitivity, and alleviated adiposity and hepatic steatosis. Mechanistically, cultured PFKFB3 knockdown HAMECs showed decreased NF-κB activation induced by PA, and consequent suppressed adhesion molecule expression and monocyte adhesion. Taken together, these results demonstrate that increased endothelial PFKFB3 expression promotes diet-induced inflammatory responses and subsequent insulin resistance, suggesting that endothelial metabolic alteration plays an important role in the development of insulin resistance.

scholarly journals CD16+ monocytes control T-cell subset development in immune thrombocytopenia

Blood ◽  
2012 ◽  
Vol 120 (16) ◽  
pp. 3326-3335 ◽  
Author(s):  
Hui Zhong ◽  
Weili Bao ◽  
Xiaojuan Li ◽  
Allison Miller ◽  
Caroline Seery ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Thrombocytopenia ◽  
Critical Role ◽  
Cell Subset ◽  
Inhibitory Effect ◽  
Cell Polarization ◽  
T Cell Subsets ◽  
Monocyte Subset ◽  
Th Cells ◽  
Ifn Γ

Abstract Immune thrombocytopenia (ITP) results from decreased platelet production and accelerated platelet destruction. Impaired CD4+ regulatory T-cell (Treg) compartment and skewed Th1 and possibly Th17 responses have been described in ITP patients. The trigger for aberrant T-cell polarization remains unknown. Because monocytes have a critical role in development and polarization of T-cell subsets, we explored the contribution of monocyte subsets in control of Treg and Th development in patients with ITP. Unlike circulating classic CD14hiCD16− subpopulation, the CD16+ monocyte subset was expanded in ITP patients with low platelet counts on thrombopoietic agents and positively correlated with T-cell CD4+IFN-γ+ levels, but negatively with circulating CD4+CD25hiFoxp3+ and IL-17+ Th cells. Using a coculture model, we found that CD16+ ITP monocytes promoted the expansion of IFN-γ+CD4+ cells and concomitantly inhibited the proliferation of Tregs and IL-17+ Th cells. Th-1–polarizing cytokine IL-12, secreted after direct contact of patient T-cell and CD16+ monocytes, was responsible for the inhibitory effect on Treg and IL-17+CD4+ cell proliferation. Our findings are consistent with ITP CD16+ monocytes promoting Th1 development, which in turn negatively regulates IL-17 and Treg induction. This underscores the critical role of CD16+ monocytes in the generation of potentially pathogenic Th responses in ITP.

scholarly journals T Helper Cells in the Immunopathogenesis of Systemic Sclerosis – Current Trends

2017 ◽  
Vol 44 (1) ◽  
pp. 57-63
Author(s):  
E. Krasimirova ◽  
D. Kyurkchiev
Keyword(s):  
Systemic Sclerosis ◽  
Peripheral Blood ◽  
Absolute Number ◽  
Inhibitory Effect ◽  
Major Effect ◽  
Autoimmune Response ◽  
T Helper ◽  
Th Cell ◽  
Cutaneous Form ◽  
Ifn Γ

Abstract Systemic sclerosis (SSc) is a chronic progressive autoimmune disease characterized by skin and multiorgan involvement with alterations in both the innate and adaptive immunities. The hallmark of the disease is widespread fibrosis engaging the skin and multiple internal organs, as well as the musculoskeletal system. There is mounting evidence that T cells are key players in the pathogenesis of scleroderma. The current review discusses the role of the different T helper (Th) lymphocyte subsets in the processes of inflammation and fibrosis, characteristics for the pathogenesis of the disease. Cytokines produced by Th cell populations have a major effect on endothelial cells and fibroblasts in the context of favoring/inhibiting the vasculopathy and the fibrosis spread. The Th2 pro-fibrotic cytokines IL-4 and IL-13 have been shown to induce collagen synthesis by fibroblasts, whereas IFN-γ demonstrates an inhibitory effect. Increased Th17 cells are present in the scleroderma skin infiltrates. The combination of IL-17, IFN-γ and TGF-β levels in CD45RO and CD45RA cells from patients with SSc is useful to distinguish between the limited and the diffuse phenotype of the disease. There are accumulating data for functional and numerical alterations in the Tregs in SSc. High levels of TNF-α which might reduce the suppressive ability of Tregs have been described. According to some studies, the number of Tregs in scleroderma skin biopsies has been decreased against the normal absolute number of Tregs in peripheral blood of the same patients, which suggests suppressed immunomodulatory response. Other studies reported increased frequency of Tregs in peripheral blood of patients with systemic sclerosis and established a correlation with disease activity. The main immunological challenge remains the identification of the trigger of the autoimmune response in SSc, the causes for preferential Th2-type cell responses and the immunological differences between the diffuse and the limited cutaneous form of the disease.

scholarly journals Toll-like receptor 9 controls anti-DNA autoantibody production in murine lupus

2005 ◽  
Vol 202 (2) ◽  
pp. 321-331 ◽  
Author(s):  
Sean R. Christensen ◽  
Michael Kashgarian ◽  
Lena Alexopoulou ◽  
Richard A. Flavell ◽  
Shizuo Akira ◽  
...  
Keyword(s):  
Autoimmune Disease ◽  
Lupus Erythematosus ◽  
Critical Role ◽  
Systemic Autoimmune Disease ◽  
Toll Like Receptor ◽  
Autoantibody Production ◽  
Nuclear Antigens ◽  
Deficient Mice

Systemic autoimmune disease in humans and mice is characterized by loss of immunologic tolerance to a restricted set of self-nuclear antigens. Autoantigens, such as double-stranded (ds) DNA and the RNA-containing Smith antigen (Sm), may be selectively targeted in systemic lupus erythematosus because of their ability to activate a putative common receptor. Toll-like receptor 9 (TLR9), a receptor for CpG DNA, has been implicated in the activation of autoreactive B cells in vitro, but its role in promoting autoantibody production and disease in vivo has not been determined. We show that in TLR9-deficient lupus-prone mice, the generation of anti-dsDNA and antichromatin autoantibodies is specifically inhibited. Other autoantibodies, such as anti-Sm, are maintained and even increased in TLR9-deficient mice. In contrast, ablation of TLR3, a receptor for dsRNA, did not inhibit the formation of autoantibodies to either RNA- or DNA-containing antigens. Surprisingly, we found that despite the lack of anti-dsDNA autoantibodies in TLR9-deficient mice, there was no effect on the development of clinical autoimmune disease or nephritis. These results demonstrate a specific requirement for TLR9 in autoantibody formation in vivo and indicate a critical role for innate immune activation in autoimmunity.

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