Fig.2 IFA results of PCV2 double copy infectious clone transfected in vitro in PK-15 cells (200×). There was number same with transfected cells. (A) 2PCV2b infectious clone. (B) 2PCV2b-6M infectious clone. (C) 2PCV2d infectious clone. (D) 2PCV2d-6Minfectious clone. (E) Empty vector.