Analysis of potential antigens of protoscoleces isolated from pulmonary and hepatic hydatid cysts of Bubalus bubalis.

The aqueous soluble proteins of the protoscoleces of Echinococcus granulosus isolated from the pulmonary and hepatic hydatid cysts of Bubalus bubalis were partially purified on Sephadex G-200 column. The isolated fractions were tested for their antigenicity by immunodot using the sera collected from experimentally infected puppies during the prepatent period of infection. Six protein profiles (F1-F6) were recovered from both the isolates but the polypeptide recovery of each fraction of the two isolates were some what different, particularly protein concentration of F5 in the liver isolate was greater than the lung isolate. Contrary to this, the concentration of F1 polypeptides of the lung origin protoscoleces is greater as compared to that of the liver. In addition, some antigenic dissimilarity has also been observed in the two isolates. A weak IgG response against F1, F2 and F6 polypeptides was observed in the 4th day post infection (p.i.) sera. With the age of infection the response against these antigens increased as revealed by the intensity of the spot in immunodot analysis. Our studies show that the differences in the elution profile and antigenic profile of the lung and liver isolates, as revealed by gel filtration and immunodot analysis, might be either due to the influence of the microhabitat or these may be two different strains. Further studies are certainly required in this direction.