The Effect of Humanized Anti-CεmX Antibody (h4B12) on IgE Production in the PBMC Isolated From Atopic Dermatitis Patients

Despite the success of Omalizumab that neutralizes free IgE in blood and interstitial fluids, treatment of many allergic disorders remains an unmet medical need. Omalizumab was approved for patients having serum IgE levels in the range of 30-700 IU/ml. Omalizumab may not be effective for patients with much higher serum IgE levels, such as those with atopic dermatitis. Therefore, an alternative approach that targets IgE-committed B cells directly and inhibits the synthesis of IgE without binding to free IgE will be attractive. Anti-CεmX mAb, developed by Dr. TW Chang in Academia Sinica, binds human mIgE+ cells, including IgE-committed lymphoblasts and memory B cells. Such anti-CεmX mAbs should be able to activate B cell receptor (BCR) signaling, which leads to anergy or apoptosis of mIgE+ B lymphoblasts, and induces ADCC through their Fc portion. Depletion of mIgE+ B cells by anti-CεmX treatment would inhibit the formation of IgE-producing plasma cells, resulting in a long-term attenuation of IgE synthesis that would eventually lead to a desensitized state in allergic patients.