Evidence for IgE immune complexes and distribution of IgG subclasses with anti-IgE activity in patients with atopic dermatitis.
The anti-IgE autoantibody was detected, using a radioimmunoassay, in 17 out of 35 (48.6%) of patients with atopic dermatitis. Significant increased levels of IgG-anti-IgE were seen in the patients studied compared with the control group. The specificity of the anti-IgE autoantibody was confirmed by competitive inhibition assay using IgG, IgM, IgE myeloma. A correlation was observed between the levels of IgG-anti-IgE and serum IgE but not between the IgG subclasses with anti-IgE activity and the clinical status. These data demonstrate that the IgG subclass distribution with anti-IgE activity belongs mostly to the IgG1 and IgG4 subclasses compared with the controls. Moreover, ultracentrifugation analysis indicated that the IgG-anti-IgE in the serum samples from the patients with atopic dermatitis was present in the form of an immune complex with self-IgE. These observations may suggest that the anti-IgE complexes may play a broader role in the modulation of the immune response and that this autoantibody may mask recognition of IgE in conventional assays.
Carini
C
C
Department of Allergology and Clinical Immunology, University of Rome La Sapienza, Italy.
Fratazzi
C
C
Aiuti
F
F
D000293:Adolescent; D000328:Adult; D000918:Antibody Specificity; D000936:Antigen-Antibody Complex / Q000032:analysis*; D001323:Autoantibodies / Q000032:analysis*; D002648:Child; D003876:Dermatitis, Atopic / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis / Q000276:immunology*; D007074:Immunoglobulin G / Q000145:classification* / Q000276:immunology; D008875:Middle Aged
D000936:Antigen-Antibody Complex; D001323:Autoantibodies; D007074:Immunoglobulin G; D007073:Immunoglobulin E