The Comparative Studies Of Recombinant Antigens On Diagnosis Of Schistosomiasis Japonicum In Cattle

Schistosomiasis japonica is a zoonosis parasitic disease that cause serious disease to humans and animals, of which, diseased cattle are the most important infection sources of schistosomiasis in our country. The basis of schistosomiasis prevention is precise diagnostic methods construction. Now existing etiology diagnostic methods have a lot of shortage, such as low detection rate, high omission factor, time and energy consuming, and can't afford the need for schistosomiasis prevention development. Serological diagnosis method is convenient and sensitive, but not good in specificity, reproducibility and stability, and can't be used for therapeutic effect exam as well as discriminate present infection from previous infection. So it is very need to research more ideal diagnostic antigens, which have more specific or sensitive, or can be discriminated present infection from previous infection, or can be used to examine therapeutic effect. Our purposes is disccussing if multivalence and multi-epitope gene recombination antigens can raise specificity and sensitivity simultaneously.By gene engineering technology, 5 schistosome gene recombinant antigens or multi-epitope gene recombinant antigens are produced, expressed and purified in our laboratory in this rearch, At the same time, schistosome soluble egg antigen SEA which is used frequently for serological diagnosis in schistosomiasis as control antigen. Application potential of different gene recombinant gene or polypepitode gene recombinant genes as diagnosis antigen are compared and analyzed in test schistosomiasis infected by bovine and rabbit by indirect ELISA.Using above 5 schistosome gene recombinant genes and SEA as diagnosis antigen, we grope and ascertain the optimizating experiment conditions of rabbit and bovine infected by schistosoma japonicum by indirect ELISA. The optimizating experiment conditions include choosing antigen, coat concentration, sealant and reaction time, serum dilutability and reaction time, enzyme-label second antibody dilutability and reaction conditions, substrate reaction condition etc. Three researches are developed on these basises.1. Different genes recombination antigens as diagnostic antigens are compared and analyzed to detect the sensitivity and specificity of rabbit and bovine post-infection by schistosomiasis.2. The gene recombination antigens obtained from the rabbits infected by Schistosoma japonicum before and after drug treatment, the condition of up and down of the antibody stimulated by gene recombination antigens as the follows.3. The research of early diagnosis antigen and technology of schistosome.The results of the research shows that the negative accordance rate of healthy animal and detection rate of bovine and rabbit infected by schistosomiasis by using bivalence multi-epitode recombinant antigen pGEX-SjGCP-Sj23 as diagnosis antigen are both higher than SEA and other gene recombinant antigens. The effect of bivalence multi-epitope recombination antigen pGEX-SjGCP-Sj23 is the best in examining curative effect and discrimination present infection from previous infection among all the antigens. The detection technology to the specific IgM antibody against pGEX-SjGCP-Sj23 is possible to used for the early diagnosis to schistosome. Bivalence multi-epitode recombinant antigen pGEX-SjGCP-Sj23 is a new schistosomiasis diagnosis antigen with application prospect and worth of deep studying.The research provids a new idea for establishment more senstive, specific domestic animal schistosoma japonicum serology diagnosis technology.