Identification and characterization of specific hydatid antigen fraction(s).

A specific hydatid antigen was prepared in this study from Echinococcus granulosus cyst in livers and lungs of camels. Elimination of host "camel" protein from crude hydatid fluid was achieved by two methods: Salting out using ammonium sulfate precipitation method and immunoaffinity purification using coupled anticamel antibody to cyanogenbromide activated sepharose 4B gel. Testing the prepared hydatid antigen against anticamel serum, using immunodiffusion method, indicated that the affinity purified hydatid antigen was almost completely purified from camel protein. Characterization of the affinity purified hydatid antigen, using immunoelectrophoresis, showed positive arc 5 precipitation when tested against known positive antihydatid sera. Further characterization with gradient gel electrophoresis, showed with silver stain that the dominant and most consistently demonstrable proteins occurred as a complex in the 52/62 KDa region. Strong reaction with the 52/62 KDa complex was consistently observed when the affinity purified hydatid antigen was probed with known positive reference antihydatid sera. The identified hydatid antigen fraction(s) with 52/62 KDa complex can provide promising non-invasive parameter for diagnosis of Hydatidosis.