The regulation of mediator release in human intestinal mast cells is largely unknown. Apart from IgE receptor crosslinking no secretagogues have been described so far. This study examined the effect of two cytokines (c-kit ligand and interleukin 3) and other agonists on human intestinal mast cell function. Cells were isolated from surgery specimens of 47 patients undergoing intestinal resection...

Bronchial epithelial cells are the first cells to come into contact with inhaled pneumoallergens. It has been suggested that these cells may play an important role in the allergic response, and indeed bronchial epithelial cells of some atopic asthmatic subjects have been shown to express the low-affinity receptor for IgE on their surface. In this report we demonstrate, using bronchial biopsies,...

Genome-wide association studies to identify loci responsible for platelet function and cardiovascular disease susceptibility have repeatedly identified polymorphisms linked to a gene encoding platelet endothelium aggregation receptor 1 (PEAR1), an "orphan" cell surface receptor that is activated to stabilize platelet aggregates. To investigate how PEAR1 signaling is initiated, we sought to iden...

Background: Secretory proteins of IgE receptor activated mast cells and basophils play a pivotal role in the generation of immediate and long term immune responses in allergy and type I hypersensitivity. Objective: The present study aims to generate a 2-D map and profile of proteins secreted from a high secretory variant of the rat basophilic leukemia cell line, RBL-2H3.1, which in view of the ...

Immunoglobulin E and its interactions with receptors FcϵRI and CD23 play a central role in allergic disease. Omalizumab, a clinically approved therapeutic antibody, inhibits the interaction between IgE and FcϵRI, preventing mast cell and basophil activation, and blocks IgE binding to CD23 on B cells and antigen-presenting cells. We solved the crystal structure of the complex between an omalizum...

A better understanding of the pathophysiological role of Langerhans cells (LC) in atopic diseases is dictated by the characterization of the structures involved in immunoglobulin (IgE)-binding on their cell surface. We previously reported that human LC express the high affinity receptor for IgE (FceRI), as well as the low affinity receptor for IgE (FceRII/CD23). In the present study, we documen...

We have used in situ electromigration and post-field relaxation (Poo, M.-m. 1981, Annu. Rev. Biophys. Bioeng., 10:245-276) to assess the effect of immunoglobulin E (IgE) binding on the lateral mobility of IgE-Fc receptors in the plasmalemma of rat basophilic leukemia (RBL) cells. Bound IgE sharply increased the receptor's electrokinetic mobility, whereas removal of cell surface neuraminic acids...

Approximately 60% of perioperative anaphylactic reactions are thought to be immunoglobulin IgE mediated, whereas 40% are thought to be non-IgE mediated hypersensitivity reactions (both considered non-dose-related type B adverse drug reactions). In both cases, symptoms are elicited by mast cell degranulation. Also, pharmacological reactions to drugs (type A, dose-related) may sometimes mimic sym...