Detection of IgG subclass-specific anti-IgE antibodies in normal and atopic individuals.

Atopic dermatitis and atopic asthma patients were shown to have elevated IgG anti-IgE levels compared with those of controls. When the pattern of IgG subclass anti-IgE activity was studied, further differences between the three groups became apparent. Adults with atopic dermatitis had elevated IgG1 and IgG4 anti-IgE compared with those of controls but no corresponding increase in the IgG2 or IgG3 subclasses. For Sri Lankan children with atopic asthma and a high incidence of Nematoda infection, elevated anti-IgE was restricted to the IgG1 subclass. While IgG1 anti-IgE proved to be the predominant subclass for both atopic groups, IgG2 anti-IgE was the major subclass among controls.