Adrenal-cortex autoantibodies and steroid-producing cells autoantibodies in patients with Addison's disease: Comparison of immunofluorescence and immunoprecipitation assays

Autoimmune Addison's disease and premature ovarian failure are characterize d by the presence of organ-specific autoantibodies. The main adrenal and go nadal autoantigens have been identified and cloned, and the relationship be tween the autoantibodies detected by immunofluorescence techniques and thos e detected by the new assays using recombinant autoantigens needed to be in vestigated. We studied 165 patients with Addison's disease: 143 patients ha d different forms of autoimmune Addison's disease (13 with idiopathic prema ture ovarian failure) and 22 had nonautoimmune Addison's disease. Adrenal-c ortex autoantibodies and steroid-producing cell autoantibodies were measure d by the immunofluorescence techniques. Autoantibodies to steroid 21-hydrox ylase, 17 alpha-hydroxylase, and P450 side chain cleavage enzyme were measu red by immunoprecipitation assay using S-35-labeled recombinant proteins. Adrenal-cortex autoantibodies and autoantibodies to 21-hydroxylase were fou nd in 81% of the patients with autoimmune Addison's disease. None of the pa tients with nonautoimmune Addison's disease had adrenal-cortex autoantibodi es or autoantibodies to 21-hydroxylase. A high association between these tw o markers in patients with different forms of autoimmune Addison's disease and in those with short- or long-standing disease was found. Steroid-produc ing cells autoantibodies were found in 26% of the patients with autoimmune Addison's disease, and autoantibodies to 17 alpha-hydroxylase and/or P450 s ide chain cleavage enzyme in 36% of the patients. Steroid-producing cells a utoantibodies were found in 11/13 (85%) of patients with idiopathic prematu re ovarian failure associated with autoimmune Addison's disease, and autoan tibodies to 17 alpha-hydroxylase and/or P450 side chain cleavage were found 12/13 (92%) of patients; the only case negative for all these three marker s suffered from Turner's syndrome. Provided that a high standard of immunofluorescence technique is maintained , measurement of adrenal cortex autoantibodies or steroid-producing cells a utoantibodies by either immunofluorescence or immunoprecipitation assay is essentially equivalent.