IgE, a target molecule for the treatment of allergy?

The concentration of circulating IgE is sufficiently low for administration of carefully selected anti-IgE antibodies to trap IgE and block its intera ctions with receptors. Anti-IgE antibodies targeted against the interaction motif of IgE and the type I receptor (Fc epsilon RT) are devoid of any ana phylactic effects, as they cannot access IgE bound by receptors. These non- anaphylactogenic antibodies have been modified to reduce murine Ige sequenc es (chimeric antibody or humanized antibody) to a minimum. Tested in precli nical and clinical trials, they reduce the quantity of free IgE available t o sensitize target cells and exert an inhibitory effect on immediate and de layed allergic bronchospastic responses. They also reduce (Fc epsilon RI) e xpression by circulating basophils and consequently their activation potent ial gy specific IgE, The long-term effects of anti-IgE antibodies on allerg ic reactions and IgE production have yet to be evaluated.