title: Dermatitis herpetiformis: immune complex detection with C1q and monoclonal rheumatoid factor.
abstract: To determine the significance of circulating immune complexes in dermatitis herpetiformis, serum samples from thirty patients with active disease were tested by a C1q binding radioassay, while serum samples from twenty-one of these patients were tested by a monoclonal rheumatoid factor (mRF) inhibition radioassay. By direct immunofluorescence, all patients demonstrated typical IgA deposition in dermal papillae. Using the C1q binding assay, only seven of forty-two serum samples had elevated C1q binding activity, while by the mRF inhibition assay, thirteen of twenty-five samples had elevated immune complex levels. Nine of these latter thirteen positive serum samples, however, were minimally elevated. Thus, IgG and/or IgM containing immune complexes are infrequently present, or at very low levels, in sera of patients with active dermatitis herpetiformis.
mesh_terms: D000936:Antigen-Antibody Complex / Q000032:analysis*; D003166:Complement Activating Enzymes / Q000276:immunology; D015922:Complement C1q; D003874:Dermatitis Herpetiformis / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D011863:Radioimmunoassay; D012217:Rheumatoid Factor / Q000276:immunology; D012867:Skin / Q000276:immunology
chemical_list: D000936:Antigen-Antibody Complex; D007070:Immunoglobulin A; D015922:Complement C1q; D012217:Rheumatoid Factor; D003166:Complement Activating Enzymes