Anti-IgE autoantibody in patients with atopic dermatitis.

The anti-IgE autoantibody in the IgG class was detected in 39/45 (86.7%) patients with atopic dermatitis by using a newly established solid-phase enzyme immunoassay. The epsilon-chain specificity of the anti-IgE autoantibody was confirmed by competitive inhibition by using human IgG, IgA, IgM, IgD, IgE, and heat-denatured IgE protein. Significant correlations were observed between the levels of the anti-IgE autoantibody and the serum IgE. Gel filtration studies indicated that the anti-IgE autoantibody in sera from atopic dermatitis was mainly present in the form of an immune complex with self IgE. The role of the IgE-anti-IgE immune complex and the role of the anti-IgE autoantibody in the modulation of the IgE-mediated immune system in atopic dermatitis are discussed.