Expression of human Streptococcus suis 2 muramidase released protein and preparation and application of its monoclonal antibodies / 中国兽医学报

ABSTRACT

The mrp gene of SS2 human strain Habb was truncated and cloned into a prokaryotic expression vector pGEX4T-2,and a fusion-expressed protein MRP-GST of 61 000 was obtained in E.coli.The GST was cut from MRP-GST with thrombin protease to gain the purified MRP of 35 000 which showed a strong reaction to the SS2 positive sera in Western blotting.BALB/c mice were immunitied intraperitoneally with purified MRP protein.Murine myeloma cells were fused with the splenocytes of the immunized mice after the third immunization.An indirect ELISA coated with purified MRP was used to screen hybridomas for production of specific antibody.The six McAb recognized MRP specially.According to the results of 71 standard strains (48 SS and 34 SS2)by Sandwich ELISA,the coincidence rate was 97.2%,but for 34 SS standard serotype was 100 %.The ELISA method has a potential value for clinical and epidemiological applicationgs.