Immunoglobulin E (IgE) has been shown to play a critical role in the allergic late-phase reaction, which is marked by intense leukocyte infiltration and edema. In this study we assessed the allergic pleural inflammation triggered by intrapleural (i.pl.) challenge in sensitized rats. We examined pleural effluent from actively sensitized rats following anti-IgE monoclonal antibody (mAb) (MARE-1) ...

Aims-To investigate the ability of circulating IgG autoanti-IgE antibodies from atopic rhinitis patients to block the binding of IgE to its low affinity receptor (FcepsilonRII), also termed CD23.Methods-This involved the use of a well validated flow cytometric method to detect inhibition of FITC labelled IgE binding to human B cells expressing CD23 (RPMI 8866 cell line).Results-Taking inhibitio...

In the mast cell signaling pathways, the binding of immunoglobulin E (IgE) to FcepsilonRI, its high-affinity receptor, is generally thought to be a passive step. In this study, we examined the effect of IgE alone, that is, without antigen stimulation, on the degranulation in mast cells. Monomeric IgE (500-5,000 ng/ml) alone increased cytosolic Ca2+ level ([Ca2+]i) and induced degranulation in r...

Activation of the high affinity IgE receptor (Fc epsilonRI) through IgE-antigen complexes induces mast cell degranulation, synthesis of lipid mediators and cytokine production. These effects are involved in Type I hypersensitivity reactions and controlling them has been the main objective of many anti-allergic therapies. Here we report that pretreatment of murine bone marrow derived mast cells ...

Heman airway preparations at resting tone were relaxed with either the leukotriene synthesis inhibitor BAY x1005 (3 muM), chlorpheniramine (1 muM) or the thromboxane receptor antagonist BAY u3405 (0.1 muM). The response to anti-IgE (1:1000) was 58 +/- 8% of acetylcholine pre-contraction (2.19 +/- 0.28 g). Indomethacin (3 muM) enhanced the anti-IgE-induced contraction by 28%. The anti-IgE maxima...

The role of the IgE-FcεRI complex in malaria severity in Plasmodium falciparum-hosting patients is unknown. We demonstrate that mice genetically deficient for the high-affinity receptor for IgE (FcεRIα-KO) or for IgE (IgE-KO) are less susceptible to experimental cerebral malaria (ECM) after infection with Plasmodium berghei (PbANKA). Mast cells and basophils, which are the classical IgE-express...

The membrane form of immunoglobulins (mIg) is expressed on the surface of B lymphocytes from a very early developmental stage in the bone marrow (pre B cell) until the cell finally differentiates into a plasma cell. mIgs associate with other transmembrane proteins to form the B cell antigen receptor complex (BCR). Numerous studies have confirmed that signaling through the BCR not only steers th...

Cross-linkage of the high-affinity immunoglobulin E (IgE) receptor (FcɛRI) on mast cells by antigen ligation has a critical role in the pathology of IgE-dependent allergic disorders, such as anaphylaxis and asthma. Restraint of intracellular signal transduction pathways that promote release of mast cell-derived pro-inflammatory mediators is necessary to dampen activation and restore homoeostasi...

BACKGROUND Atmospheric pollution may play a role in the immune response to allergens either directly or by entering the food chain. While particulate platinum group elements (PLGE) emitted by catalytic converters can be considered biologically inert, approximately 10% of these species accumulate in the environment as bioavailable soluble forms. METHODS We challenged in vitro human immature an...

Stereo-specific perturbation of the IgE-receptor (shown in previous studies) produces a monophasic rise in cyclic AMP that peaks at 15 s and a depletion of cyclic AMP-dependent protein kinase that plateaus at 30-60 s. The previously observed linear relationship between the attenuation in the monophasic rise in cyclic AMP and the quantity of mediator release in the presence of incremental concen...