猪圆环病毒2型Cap蛋白单克隆抗体的制备与鉴定OA北大核心CSTPCD

This study aims to prepare monoclonal antibody(mAb)to capsid(Cap)protein of porcine circovirus type 2(PCV2),and to the develop and apply immunological diagnostic methods.First,PCV2 Cap protein was expressed in Escherichia coli,and the purified Cap protein was assembled into virus-like particles(VLPs)in vitro.BALB/c mice were immunized with VLPs.Hybridoma cell technology was used to screen hybridoma cell lines that could secrete monoclonal antibodies against PCV2 Cap protein statically.Monoclonal ascites were further prepared and purified,and the specificity of monoclonal antibodies was identified by Western-blot and IFA methods.Forty-five short peptides covering the full length of PCV2 Cap protein were synthesized by stepwise interception method,and the epitope regions recognized by monoclonal antibodies were identified by indirect ELISA.Two strains of mAbs were used to detect and identify PCV2 in lung tissues of clinically infected pigs by immunohistochemistry(IHC).Twom Abs(1A6 and 1A8)were obtained,and mAb1A6 and 1A8 belong to IgG2b and IgG1 subclass,respectively,both had κ light chain.The titers of these two mAbs were 1∶656 100,respectively.IFA results showed that both mAbs could react specifically with PCV2-infected PK-15 cells.Western-blot results showed that both strains of mAbs reacted specifically with PCV2 Cap protein,and did not cross-react with PCV3 and PCV4 Cap protein.Both mAbs could recognize the 211-225 aa peptide at C-terminal of PCV2 Cap protein.IHC results showed that both mAbs could specifically recognize PCV2-infected clinical samples.In this study,2 mAbs(1A6 and 1A8)were successfully obtained,both of which can recognize PCV2 Cap with good specificity,providing important biological materials for the establishment of PCV2 immunological diagnostic method and the study of biological function of PCV2 Cap protein.