Characterization of immunogenic Clonorchis sinensis protein fractions by gel filtration chromatography

ObjectiveTo characterize immunogenic protein fraction of Clonorchis sinensis (C. sinensis) by partial purification.MethodsA total of 30 hamsters were infected with 50 C. sinensis metacercariae, and then C. sinensis protein was purified by gel filtration chromatography. Indirect ELISA and immunoblot were used to detect the antibody in sera of hamsters infected with C. sinensis.ResultsThe gel filtration showed 2 peaks at high (fraction No. 10 to 14) and low (fraction No. 21 to 26) molecular weight proteins. Indirect ELISA showed both antibodies of clonorchiasis and opisthorchiasis reacted strongly with early fractions (6 to 14) and gradually reduced at middle and late fractions (15 to 50). Both antibodies showed different individual fraction of C. sinensis by immunoblot. It showed several protein bands which the 34 and 37 kDa were major proteins. The 53 kDa protein which was only found in the clonorchiasis reacted with fraction 20.ConclusionsThe purified antigen of C. sinensis reacted similar with both antibodies of clonorchiasis and opisthorchiasis where strong reaction was seen with early fractions. The C. sinensis protein fraction No. 20 may be useful for immunodiagnosis of clonorchiasis.