[Detection of circulating antibodies in the blood and immune complex precipitates of patients with autoimmune diseases (preliminary report)].

Antibodies against ENA (Extractable Nuclear Antigens), SSA/Ro and SSB/La were investigated in parallel in the serum and the immune complex precipitates of 41 patients with autoimmune disease (10 systemic lupus erythematosus, 23 discoid lupus erythematosus, 3 subacute cutaneous lupus erythematosus, and 5 progressive systemic sclerosis). It was demonstrated that in some cases the autoantibody spectrum of the serum did not coincide with that of the immune complex precipitate. In the majority of patients the protein content of isolated immune complexes was increased and the increase was attributed to IgG solely. In some patients antibodies appeared not only in the serum but also in immune complex, even in 4 patients (2 systemic lupus erythematosus, 1 subacute cutaneous lupus erythematosus, and 1 progressive systemic sclerosis) antibodies were detected only in the immune complex precipitate.