Search results for "regulator"

Regulation of IgE production and airway reactivity by CD4(-)CD8(-) regulatory T cells

2015

The mechanisms of tolerance induction occurring in the course of allergen-specific immunotherapy have not been elucidated in full detail. Our study aimed to characterize high zone tolerance in mouse models of type I allergy and of allergic airway inflammation induced by subcutaneous sensitization of mice with high doses of the model allergen ovalbumin (OVA) without the use of adjuvant. Mice were immunized by subcutaneous injection of high doses (HD) of OVA or, for comparison, low doses (LD) of OVA in saline. HD-mice showed lower specific IgE, but augmented IgG in sera than LD-mice. Pre-treatment of mice with HD-OVA antigen-specifically inhibited IgE production subsequently induced by LD-OVA…

Understanding the complexity of IgE-related phenotypes from childhood to young adulthood: A Mechanisms of the Development of Allergy (MeDALL) seminar.

2012

Mechanisms of the Development of Allergy (MeDALL), a Seventh Framework Program European Union project, aims to generate novel knowledge on the mechanisms of initiation of allergy. Precise phenotypes of IgE-mediated allergic diseases will be defined in MeDALL. As part of MeDALL, a scientific seminar was held on January 24, 2011, to review current knowledge on the IgE-related phenotypes and to explore how a multidisciplinary effort could result in a new integrative translational approach. This article provides a summary of the meeting. It develops challenges in IgE-related phenotypes and new clinical and epidemiologic approaches to the investigation of allergic phenotypes, including cluster a…

Technical advance: Soluble OX40 molecule mimics regulatory T cell modulatory activity on FCεRI-dependent mast cell degranulation

2011

ABSTRACT Tregs play a central role in modulating FcɛRI-dependent MC effector functions in the course of the allergic response. Cellular interaction depends on the constitutive expression of OX40 on Tregs and the OX40L counterpart on MCs. Study of OX40L signaling on MCs is hampered by the need of a highly purified molecule, which triggers OX40L specifically. We now report that sOX40 mimics the physiological activity of Treg interaction by binding to activated MCs. When treated with sOX40, activated MCs showed decreased degranulation and Ca++ influx, whereas PLC-γ2 phosphorylation remained unaffected. Once injected into experimental animals, sOX40 not only located within the endothelium but a…

Effective treatment of allergic airway inflammation with Helicobacter pylori immunomodulators requires BATF3-dependent dendritic cells and IL-10

2014

The prevalence of allergic asthma and other atopic diseases has reached epidemic proportions in large parts of the developed world. The gradual loss of the human indigenous microbiota has been held responsible for this trend. The bacterial pathogen Helicobacter pylori is a constituent of the normal gastric microbiota whose presence has been inversely linked to allergy and asthma in humans and experimental models. Here we show that oral or i.p. tolerization with H. pylori extract prevents the airway hyperresponsiveness, bronchoalveolar eosinophilia, pulmonary inflammation, and Th2 cytokine production that are hallmarks of allergen-induced asthma in mice. Asthma protection is not conferred by…

Alternative respiratory pathways of Escherichia coli: energetics and transcriptional regulation in response to electron acceptors

1997

AbstractThe electron-transport chains of Escherichia coli are composed of many different dehydrogenases and terminal reductases (or oxidases) which are linked by quinones (ubiquinone, menaquinone and demethylmenaquinone). Quinol:cytochrome c oxido-reductase (`bc1 complex') is not present. For various electron acceptors (O2, nitrate) and donors (formate, H2, NADH, glycerol-3-P) isoenzymes are present. The enzymes show great variability in membrane topology and energy conservation. Energy is conserved by conformational proton pumps, or by arrangement of substrate sites on opposite sides of the membrane resulting in charge separation. Depending on the enzymes and isoenzymes used, the H+/e− rat…

Effects of a new IGR-ovicide on a heteropteran (Oncopeltus fasciatusDallas) and lepidopteran (Manduca sextaJohansen) insect

1987

A new insect ovicide (Ov. 165049), 4-methoxy-benzoic acid propargylester, synthesized by BASF (Ludwigshafen) was tested on Oncopeltus fasciatus and Manduca sexta. In the case of O. fasciatus also the effects on last-instar larvae and adult bugs were studied. Topical application of 40 μg/larva dissolved in acetone caused a mortality exceeding 50% at day 1 after treatment. The few animals which developed into imagines did not reproduce. A treatment with 4 μg/larva had no severe impact on metamorphosis and reproduction. Adult O. fasciatus received doses of 40 μg, 20 μg and 4 μg per animal. The high dose caused mortality of 50% at day 1 as in larvae. Mating and egg deposition did not occur in s…

Resveratrol as a Gene Regulator in the Vasculature

2014

Resveratrol (3,5,4'-trihydroxy-trans-stilbene) possesses multiple protective properties in the vasculature, including anti-oxidative and anti-inflammatory effects and improvement of endothelial function. A substantial part of these effects is attributable to gene expression changes induced by the compound. Resveratrol can activate the NAD-dependent deacetylase sirtuin 1 (SIRT1), leading to deacetylation of SIRT1 target molecules such as NF-kB and forkhead box O (FOXO) transcription factors. The inhibition of NF-kB by resveratrol reduces the expression of inflammation mediators. FOXO factors are implicated in the upregulation of antioxidant enzymes and the endothelial-type nitric oxide synth…

Chemotherapy and immunomodulation: from immunogenic chemotherapies to novel therapeutic strategies.

2013

Generation of monoclonal antibodies against human regulatory T cells.

2009

Abstract Natural CD4 + CD25 + Foxp3 + regulatory T cells (Tregs) control the activation of the immune system and therefore have become a major area of research in immunology. The generation of monoclonal antibodies against human Tregs offers the possibility to discover novel Treg-specific or Treg-associated surface markers and to identify targets for a therapeutic modulation of Tregs. Here we present a methodology optimized to efficiently induce and select mAb against human Tregs by repeated immunization of mice with Tregs from a single donor and a differential two-step flow cytometry-based hybridoma screening procedure.

Pathological role of IL-6 in the experimental allergic bronchial asthma in mice.

2005

Although allergic asthma was described to be associated with the presence of mucosal T helper (Th)2 cells, it is not entirely clear which factors are responsible for priming of T cells to differentiate into Th2 effector cells in this disease. Interleukin (IL)-6 has been recognized as important because it is secreted by cells of the innate immunity and induces the expansion of the Th2 effector cells, which are major players of the adaptive immune responses. Additionally, IL-6 released by dendritic cells (DCs) inhibits the suppressive function of CD4+CD25+ T regulatory cells, thus inhibiting the peripheral tolerance. The signal transduction of IL-6 has recently taught us how this cytokine inf…