PARTIAL CHARACTERIZATION OF ANTIGENS IN CIRCULATING IMMUNE-COMPLEXES IN CYSTIC HYDATID PATIENTS TREATED WITH ALBENDAZOLE

Immune complexes were precipitated by 3% polyethylene glycol (PEG) from 4 sera from albendazole-treated hydatid patients from Uruguay, and together with sheep hydatid cyst fluid were analysed by ion-exchange fast protein liquid chromatography (FPLC). FPLC-eluted fractions of serum preparations and cyst fluid were tested in an enzyme-linked immunosorbent assay for the detection of specific Echinococcus granulosus antigens and also for presence of specific immunoglobulin (Ig) M and IgG in the serum samples. Two peaks (nos 13 and 25) were found to have antigenic activity. Antigens were identified in both serum and cyst fluid preparation (fraction 25) after sodium dodecyl sulphate-polyacrylamide gel electrophoresis immunoblotting analysis, with approximate molecular masses 50 kDa and 62 kDa. Specific IgM antibody was also detected in the same FPLC fraction (no. 25) of PEG-precipitated serum complexes.