Abstract: ObjectiveTo establish a novel enzyme-linked immunosorbent assay(ELISA)method,namely immunomagnetic microspheres(IMMS)-ELISA,to detect specific IgG in hemorrhagic fever patients with renal syndrom(HFRS).MethodsThe recombinant nucleocapsid protein(rNP)of SEO hantavirus was expressed by the recombinant strain,E.coli BL21(DE3)/pET32a-L99S.Purified rNP was used as an antigen to establish three ELISA methods,including indirect ELISA,capture ELISA and IMMS-ELISA,for the detection of specific IgG in HFRS patients.The results of the three methods were compared with each other.ResultsThe sensitivity and specificity of the three ELISA methods were all higher than 90% and their coincidence rates were all higher than 95%.The sensitivity of indirect ELISA was 100%,but its false positive rate was 10%.The specificity of capture ELISA was 100%,but its sensitivity was lower(92.5%)than that of other two methods.The sensitivity and specificity of IMMS-ELISA were all 100%.ConclusionIMMS-ELISA is a simpler, safer,and more accurate than indirect and capture ELISA method,and easy to use in grassroots public health and clinical medical institutions.