Expression of Truncated NSP2 Protein of Porcine Reproduction and Respiratory Syndrome Virus in E.coli and Preparation of Monoclonal Antibodies Against NSP2 Protein / 中国生物工程杂志

ABSTRACT

The NSP2 gene of porcine reproductive and respiratory syndrome virus (PRRSV)S1 strain was partly amplified and cloned into a prokaryotic expression vector pGEX-6P-1 and a fusion protein GST-tNSP2 with molecular weight of 50 kDa was expressed in E.coli. The purified GST-tNSP2 protein showed a strong reaction with the PRRSV-positive sera in Western blot assay. Balb/c mice were immunized with the purified protein, and the splenocytes of the immunized mice were fused with murine myeloma cells SP2/0. After subcloning by 3 times, two hybridoma clones which produced McAbs steadily were screened by ELISA, named 3H3 and 2B5. They all reacted strongly with the PRRSV S1 infected Marc-145 cells in IFA, but not with the PRRSV SY0608 strain. Both of the McAbs belong to IgG1 isotype, and their light chains belong ? type. The expressed GST-tNSP2 protein and McAbs could be used for identification of PRRSV isolates and functional analysis of NSP2.