Constructing Animal Model Vaccinated By UV-attenuated Cercariae Of Schitosoma Japonicum And Preliminarily Screened Potential Protective Antigen

To search novel effective protective antigen against schistosoma,we set up successftilly two animal models immunized with ultraviolet-atteunated cercariae of Schistosoma japonicum.Comparing immunized rabbit serum with infected rabbit serum,the target antigens SCA 1 O4KDa and SCA 60 KDa were screened in the present study using immunoblotting. In mice model, BABL/c mice were immunized once or twice at four- week interval with 300 uv- irradiated cercaria of Schistosomajaponucirm at a dose of 400 i-i w/cm2/min. As a result 44.2% and 45.7% resistantance to infection cercariae were produced.The result showed that the conditions of immunization could induce effective immune response. Based on the immunol conditions obtained from mice,sera from multiply immunized rabbits were transferred to mice and confered it 50.9% resistance against challenging infection.It suggested that it was a good way to screen protective antigen using immunized rabbit sera ,which induce significant resistance agaist schistosoma. Western blot analysis suggested that immunized sera specifically recognized a SCA 104 KDa and a SCA 60 KDa antigen which showed an enhanced reactivity with immunized rabbit sera in comparison with infected rabbit sera. Conclusion: Effective immunol protection against Schistosoma japonicum can be induced successfully under the condition that mice were immunized once or twice with 300 uv-attenuated cercariae at the dose of 400 i-i w/cm2/min.Comparing immunized rabbits sera with infected rabbit sera ,two molecules SCAI O4KDa and SCA6OKDa were screened preliminarily and might be correlated with protection against S.japonicum. Further research is needed for the two potential protective antigen candidates.