FCERI

BACKGROUND: Treatment of patients with asthma or food allergy with omalizumab results in several consistent changes in circulating basophils. The multiple basophil phenotypes observed in patients with chronic spontaneous urticaria (CSU) present some unique attributes that may not respond in a similar fashion to patients with asthma or food allergy. As part of a clinical study on the therapeutic outcomes of omalizumab treatment in CSU, the basophil compartment was examined for changes in characteristics predicted by prior studies...

BACKGROUND: The IgE-mediated activation of mast cells and basophils results in the secretion of many substances, including the release of FceRI-alpha subunit. This released alpha subunit can bind IgE and it may act as a down-regulator of subsequent IgE-dependent reactions. However, previous studies do not observe loss of the mass of FceRI-alpha associated with the cells, at least not for human basophils. This study was designed to understand the basis for the discordant observations. METHODS: Purified human basophils were stimulated with multiple activating secretagogues and supernatants were examined for histamine and released FceRI-alpha...

OBJECTIVE: Immunoglobulin E (IgE) and its receptor, FcɛRI, importantly contribute to the pathophysiology of chronic spontaneous urticaria (CSU). Recent findings point to a possible role of total IgE as a marker of CSU disease activity, endotypes, and responses to treatment. The evidence in support of total IgE included in the diagnostic workup of patients with CSU has not yet been reviewed. METHODS: Publications were searched via PubMed. The search terms used were "chronic urticaria" and "total IgE...

Mast cells and IgE are most familiar as the effectors of type I hypersensitivity reactions including anaphylaxis. It is becoming clear however that this pair has important immunomodulatory effects on innate and adaptive cells of the immune system. In this purview, they act as endogenous adjuvants to ignite evolving immune responses, promote the transition of allergic disease into chronic illness and disrupt the development of active mechanisms of tolerance to ingested foods. Suppression of IgE-mediated mast cell activation can be exerted by molecules targeting IgE, FcɛRI or signaling kinases including Syk, or by IgG antibodies acting via inhibitory Fcγ receptors...

Atopic dermatitis (AD) is an allergic and chronic inflammatory skin disease. The present study investigates the anti-allergic, antioxidant, and anti-inflammatory activities of the ethanolic extract of Cornus officinalis (COFE) for possible applications in the treatment of AD. COFE inhibits the release of β-hexosaminidase from RBL-2H3 cells sensitized with the dinitrophenyl-immunoglobulin E (IgE-DNP) antibody after stimulation with dinitrophenyl-human serum albumin (DNP-HSA) in a concentration-dependent manner (IC50 = 0...

Paeoniflorin (PF), a monoterpene glycoside isolated from the aqueous extract of the Chinese herb Radix Paeoniae Alba, has been used for treating various inflammatory diseases. In this study, we aimed to investigate the anti-allergic activities of PF. The anti-anaphylactic activity of PF was investigated using mast cell (MC) degranulation assay as well as Ca2+ influx in vitro and skin swelling and extravasation assays in vivo. The results showed that PF inhibited MC degranulation (histamine release from 74.5 ± 4...

A high-speed fluorescence microscope operating at a 490 Hz frame rate was used to image two different membrane proteins- the high-affinity IgE receptor FcɛRI, a transmembrane protein, and an outer-leaflet GPI-anchored protein. The IgE receptor was imaged via IgE labeled with Janelia Fluor 646 and the GPI-anchored protein was imaged using a GPI-GFP fusion protein and an ATTO 647 N labeled anti-GFP nanobody. Data was collected for both proteins in untreated cells and cells that had actin stabilized by phalloidin...

Killer immunoglobulin-like receptor (KIR) 2DL4 (CD158d) was previously thought to be a human NK cell-specific protein. Mast cells are involved in allergic reactions via their KIT-mediated and FcɛRI-mediated responses. We recently detected the expression of KIR2DL4 in human cultured mast cells established from peripheral blood of healthy volunteers (PB-mast), in the human mast cell line LAD2, and in human tissue mast cells. Agonistic antibodies against KIR2DL4 negatively regulate the KIT-mediated and FcɛRI-mediated responses of PB-mast and LAD2 cells...

Basophils are rare granulocytes and dysregulated functions of these cells are associated with several atopic and non-atopic allergic diseases of skin, respiratory system and gastrointestinal tract. Both cytokines and immunoglobulin E (IgE) are implicated in mediating the basophil activation and pathogenesis of these disorders. Several reports have shown that healthy individuals, and patients with allergic disorders display IgG autoantibodies to IgE and hence functional characterization of these anti-IgE IgG autoantibodies is critical...

Rhodomyrtus tomentosa was reported to contain various bioactive metabolites, especially phenolic compounds. In the present study, the suppressive activity of phenolic compound from R. tomentosa fruits on mast cell activation was investigated in vitro. The result showed that myricetin was isolated from R. tomentosa fruits and its characterization was identified by nuclear magnetic resonance spectroscopy. Notably, myricetin was found to be effective in inhibition of mast cell degranulation by attenuating the release of β-hexosaminidase and the elevation of intracellular calcium...

Asthma is chronic inflammation of the airways characterized by airway hyper-responsiveness, wheezing, cough, and dyspnea. Asthma affects >350 million people worldwide. The Th2 immune response is a major contributor to the pathophysiology of asthma. Targeted therapy modulating cell signaling pathways can be a powerful strategy to design new drugs to treat asthma. The potential molecular pathways that can be targeted include IL-4-IL-13-JAK-STAT-MAP kinases, adiponectin-iNOS-NF-κB, PGD2-CRTH2, IFNs-RIG, Wnt/β-catenin-FAM13A, FOXC1-miR-PI3K/AKT, JNK-Gal-7, Nrf2-ROS, Foxp3-RORγt, CysLTR, AMP, Fas-FasL, PTHrP/PPARγ, PAI-1, FcɛRI-LAT-SLP-76, Tim-3-Gal-9, TLRs-MyD88, PAR2, and Keap1/Nrf2/ARE...

OBJECTIVES: To review the efficacy of anti-IgE therapy in allergic rhinitis (AR). METHODS: Literature search was performed using the PubMed and Proquest Central databases at Kırıkkale University Library. RESULTS: Although the skin prick testing in patients suffering from AR is positive (indicating that antigen-specific Immunoglobulin E has been produced), there is no association with overall circulating IgE levels. Correlation was lacking between circulating IgE level and either skin prick tests or laboratory testing for specific IgE...

Maternal IgE passes through the placenta in the form of immune complexes with anti-IgE IgG in mice. However, skin mast cells in neonates are not sensitized by the transferred IgE due to their low expression level of FcɛRI.

The anti-allergic effect of berberine was evaluated in cellular and animal models of allergic responses. In this study, the results of the in vitro model of immunoglobulin (Ig) E-mediated mast cell degranulation showed that berberine significantly inhibited the release of β-hexosaminidase (β-HEX), histamine, IL-4 and TNF-α in rat basophilic leukemia cells (RBL-2H3 cells). Pretreatment with berberine prevented morphological changes in IgE-stimulated RBL-2H3 cells such as the recovery of an elongated shape...

This study is to investigate the effects of imperatorin (IMP) on allergic responses mediated by mast cells, both in vitro and in vivo . Passive cutaneous anaphylaxis (PCA) model was established. Histological detection was performed to assess the ear histology. ELISA and Western blot analysis were used to detect the levels of corresponding cytokines and signalling pathway proteins. IMP decreased the leakage of Evans blue and the ear thickness in the PCA models, in a dose-dependent manner, and alleviated the degranulation of mast cells...

Activated mast cells (MCs) secrete a number of compounds including pro-inflammatory and anti-inflammatory cytokines. MCs are a potential source of cytokines and chemokines which participate in allergic reactions and inflammation. MCs can be activated by IgE through its receptor FceRI, but also by Toll-like receptors and/or interleukin (IL)-1. MCs can be a target for both pro-inflammatory and anti-inflammatory cytokines. IL-1 activates MCs to release inflammatory chemical mediators, and cytokines/chemokines, an effect which can be potentially inhibited by IL-37...

Mast cells (MCs) are hematopoietic immune cells commonly found in adjacent to blood vessels in the lamina propria of airway mucosa. They are important in allergic reactions since the cross-linking of their surface high affinity receptor FceRI induces activation of these cells, and provokes the synthesis, degranulation and release of inflammatory mediators including arachidonic acid-derived eicosanoids (de novo synthesized), stored enzyme mediators, and inflammatory TH1 and TH2 cytokines, and chemokines. Interleukin (IL)-33 participates in innate and adaptive immunity and inflammation and, acting on CD34+ cells, causes MC differentiation and maturation...

BACKGROUND: The soluble isoform of FcɛRI, the high-affinity IgE receptor (sFcεRI), is a protein of the IgE network with poorly defined functions. OBJECTIVE: To define cellular sources and signals that result in the production of human sFcεRI and study its in vivo functions. METHODS: FcεRI-transfected human cell lines (MelJuso), human monocyte-derived dendritic cells (moDCs), and murine bone marrow-derived mast cells (MC) were stimulated by FcεRI cross-linking and release of sFcεRI was analyzed (ELISA, Western Blot)...

BACKGROUND: Donor-specific antibodies of the IgG isotype are measured routinely for diagnostic purposes in renal transplant recipients and are associated with antibody-mediated rejection and long-term graft loss. OBJECTIVE: This study aimed to investigate whether MHC-specific antibodies of the IgE isotype are induced during allograft rejection. METHODS: Anti-MHC/HLA IgE levels were measured in sera of mice grafted with skin or heart transplants from various donor strains and in sera of kidney transplant patients with high levels of HLA IgG...

Mononuclear phagocytes (MPs) are important immune regulatory cells in atopic dermatitis (AD). We previously identified 6-sulfo LacNAc-expressing monocytes (slanMo) as TNF-α- and IL-23-producing cells in psoriatic skin lesions and as inducers of IFN-γ-, IL-17-, and IL-22-producing T cells. These cytokines are also upregulated in AD and normalize with treatment, as recently shown for dupilumab-treated patients. We here asked for the role of slanMo in AD. Increased numbers of slanMo were found in AD skin lesions...