Recombinant soluble form of the high-affinity IgE receptor α subunit and anti-IgE antibody inhibit IgE synthesis by IgE-expressing B cells through distinct pathways

Inhibition of IgE Activity to Bind its High Affinity Receptor (FcεRIα) by Mouse Anti-IgE Cε3∼4 Monoclonal Antibody (QME5)

Using computer-guided homology modeling method, the 3-D structure of the Fv fragment of a functional anti-IgE antibody (MAE11) was constructed and the spatial structure of E24-MAE11 complex was modeled based on the crystal structure of IgE-Fc (abbr. E24) and molecular docking method. Then the identified epitope of IgE was determined theoretically, which showed the key role of IgE-Cɛ3 in interac...

Inhibition of IgE and IgE/anti-IgE mediated responses in mast cells by Omalizumab

Results Omalizumab (10 ug/mL) inhibited IgE binding to LAD2 cells by 78% (P=0.007) compared to untreated control. Omalizumab (10 ug/mL) further blocked IgE-dependent upregulation of FcεRI expression by 90% (P=0.03). In addition, omalizumab removed FcεRI-bound IgE in a time-dependent manner; an effect that was detected as early as 24 hrs (57% removal; P<0.001) after addition of omalizumab result...

Suppression of IgE B Cells and IgE Binding to Fc RI by Gene Therapy with Single-Chain Anti-IgE

Purification and characterization of human recombinant IgE-Fc fragments that bind to the human high affinity IgE receptor.

The Fc-region of immunoglobulin E (IgE) comprising C epsilon 2, C epsilon 3, and C epsilon 4 domains is sufficient for binding to the alpha chain of the high affinity IgE-Fc receptor (Fc epsilon RI alpha). In order to identify the smallest Fc fragment capable of binding to the Fc epsilon RI alpha with high affinity, various regions of the IgE-Fc molecule were expressed in COS cells and investig...

A Soluble Form of the High Affinity IgE Receptor, Fc-Epsilon-RI, Circulates in Human Serum

Soluble IgE receptors are potential in vivo modulators of IgE-mediated immune responses and are thus important for our basic understanding of allergic responses. We here characterize a novel soluble version of the IgE-binding alpha-chain of Fc-epsilon-RI (sFcεRI), the high affinity receptor for IgE. sFcεRI immunoprecipitates as a protein of ∼40 kDa and contains an intact IgE-binding site. In hu...