Abstract: Objective To establish and apply a ELISA method for detecting the toxoplasma antibodies by recombinant antigen in guinea pig. Methods ELISA plates were coated using optimized recombinant toxoplasma antigen. we then determine optimal HRP-conjugated IgG concentration and test the assays specificity, sensitivity, stability and repeatability. Results The optimal HRP-IgG concentration is 1∶8000. There is no cross reaction when guinea pig sera with LCM, SV, PVM and Reo3 antibodies positive were added. The control positive serum could be detected at a maximum dilution of 1∶2560. Stability tests within six monthes show that the relative deviation of A₄₉₀ is less than 15%. The coefficient variation of the same batch is 5.7%-9.5%, of different batches is 1.9%-9.0%. The tox antibodies positive rate of 182 samples is 7.14%(13/182). The results coincidence rate between the assay and IFA is 100%, the positive coincidence is 92.3% and then negative is 100% compared to commercial kit. Conclusion The ELISA based on recombinant tox antigen can be used for routine test of guinea pig tox antibodies and be popularized.

Key words: Guniea pig, Toxoplasma, Recombinant antigen, ELISA