Short communicationHighly permissive subclone of the porcine kidney cell line for porcine circovirus type 2 production

This study established a highly permissive and decontaminated cell line for growing porcine circovirus type 2 (PCV2). A porcine kidney-15 cell line (PK-15) contaminated with porcine circovirus type 1 (PCV1) was decontaminated by neutralizing with rabbit anti-PCV1 hyperimmune serum. Subsequently, by limiting dilution and cell subcloning, four PCV1-free monoclonal cells were grown to monolayers. Each cell clone and PK-15 cell were infected with PCV2. The PKKC cell clone yielded up to 106.8 TCID50/ml at 6 days post-infection. In addition, PKKC was free of extraneous viral contamination and exhibited a cytopathic effect (CPE) to PCV2 at 6 days post-infection. The advantages of the PKKC cell are that it can grow a high PCV2 titer and exhibit CPE; therefore, it can be used for PCV2 cultivation, vaccine production, and diagnostic purposes.

► A method to clean-up PCV1 contamination from PK-15 was developed. ► By cell cloning of heterogeneous PK-15, a homogeneous daughter cell PKKC was derived. ► PKKC cells were highly permissive to PCV2 infection and produced high PCV2 titer. ► PKKC cells showed cytopathic effect 6 days after PCV2 infection.