The Antigen Analysis Of Eperythrozoon Suis And Development Of Indirect ELISA

To realize the antigen trait of Eperythrozoon suis, we developed three kind of assay to extract E.suis. We used the ultrasonic wave to deal with E.suis and obtained the polypide antigen of E.suis. The polypide antigen was purified by Sephadex G-200 and then the peak of specific protein was located by Counter Immunoelectrophoresis(CIEP). The purified antigen and polypide antigen of E.suis were analyzed use SDS-PAGE and Western blotting. At the same time we extracted the secretory antigen of E.suis from the vitro culture solution and the secretory antigen was compared with polypide antigen. There were four protein binds of polypide antigen and the molecular weight was 77kD, 62kD, 58kD, 29kD,respectively. The specific antigen molecular weight was 58kD and 29kD. The secretory antigen only has a protein bind and its molecular weight was 29kD. The results indicated that the specific antigen and the secretory antigen both have better reactionogenicity.We also developed the indirect ELISA to detect E.suis antibodies for consummate the serodiagnosis methods. The results showed that the working concentration of the antigen is no lower than the 5 μg/ml, the positive serum do 1:160 dilutions, the conjugate's optimal dilution was 1:4 000 instillations, the effective examine is the best. The method has no cross-reaction with Mycoplasma hyopneumoniae, Swine fever and Swine toxoplasmosis serm. The indirect EL1SA and indirect hemagglutination test (IHA) parally were to detect E suis antibodies in 118 swine serm samples. The results indicated that the indirect ELTSA is more specific than IHA, the electropositive rate is higher 19.5 than 1HA. And the electropositive accordance rate of indirect ELISA and IHA is 100%. The research can be used to detect E suis antibodies in swine serm, rapidly, specificly and stably.