SPECIFIC RECOGNITION OF HYDATID CYST ANTIGENS BY SERUM IGG, IGE, AND IGA USING WESTERN-BLOT

Diagnosis of hydatid disease in humans relies on the detection of spec ific antibodies against antigens of the metacestode from Echinococcus granulosus, The specificity and sensitivity of current immunological t echniques based on specific serum IgG rely on the way antigens are pur ified. We used Western immunoblotting to detect specific IgG, IgE, and IgA antibodies in serum from patients with hydatid disease using eith er crude antigen preparations (total hydatid fluid), purified fraction s enriched in Antigens 5 and B, and glycoproteins from hydatid fluid. Depending on whether crude HF or purified antigen fractions were used, IgG and IgE recognized specifically low-to-medium MW bands between 12 and 42 kDa. IgA recognized specifically 110 kDa band in crude hydatid fluid and in the glycoprotein fraction of hydatid fluid, and a 42 kDa band in ail antigen samples used. Besides the advantage of detecting specific IgA in crude hydatid fluid, these results offer the possibili ty of simplifying future immunological tests if specific secretory IgA can be similarly detected. (C) 1997 Wiley-Liss, Inc.