[Circulating immune complexes in the serum of tumor patients].

The conditions for the detection of circulating immune complexes (CIC) were established by combination of polyethylene glycol precipitation with a nephelometric determination on the precipitate of endogenous C1q. The CIC precipitated from the sera of patients with breast carcinoma, malignant melanoma or autoimmune diseases were dissociated in SDS-beta-mercaptoethanol buffer and no differences were observed in the electrophoretic patterns os polyacrylamide gels allowing to characterize tumour specific antigens.