In order to construct cell lines without CD163gene,agene of porcine reproductive and respiratory syndrome virus receptor,and find out role of CD163in PRRSV infection,5'and 3'homologous arms of CD163gene of porcine reproductive and respiratory syndrome virus receptor were amplified and cloned into pGEM-T vector.Results of sequencing showed that 5'and 3'homologous arms of CD163gene were 4.5kb and 1.1kb,respectively.Then,the homologous arms of CD163gene were subcloned into pSSC-9to construct a targeting vector pSSC-Larm-Sarm for CD163gene knock-out.The vector will be used to construct fibroblast cells with CD163gene knockout.

In order to develop effective detection methods and prepare monoclonal antibody of porcine circovirus type Ⅱ , Cap and Rep genes of porcine circovirus type Ⅱ were amplified and cloned into pMD18-Tsimple vector. And the genes were sequenced. Then Cap and Rep genes were sub-cloned into pACYCDuet-1 vector to generate three prokaryotic expression plasmids named pACYCDuet-1-Cap, pACYCDuet-1-Rep, and pACYCDuet-1-Rep -Cap. The plasmids were transformed into E.coli BL21 (DE3) and expressed. The results of Western-blotting showed that the two proteins were expressed successfully in E. coli BL21 (DE3). Furthermore, plasmid for coexpression of two proteins expressed better than the other two plasmids.