Optimal transfection methods and comparison of PK-15 and Dulac cells for rescue of chimeric porcine circovirus type 1-2

Abstract

A chimeric porcine circovirus type 1-2 (PCV1-2) infectious DNA clone has low transfection efficiency and exhibits low levels of proliferation. Electroporation and lipofection parameters were optimized for PK-15 and Dulac cells with the purpose of increasing the efficiency for rescuing infectious PCV1-2. Titers of PCV1-2 in Dulac cells were 100-fold higher than those in PK-15 cells following transfection. The electroporation efficiency into Dulac cells was high when three 400μs pulses at 250V with 6μg of plasmid DNA was used, lipofection efficiency was high when the ratio of DNA to transfection reagent was 1:3. The proportion of infected cells was 55.6% compared with 44.2%, for the electroporation and lipofection techniques respectively. Virus titers were higher in Dulac cells, from 104.44 to 105.32TCID50/mL compared with 101.90–103.38TCID50/mL for PK-15 cells. Dulac cells were more permissive to PCV1-2 than PK-15 cells regardless of the transfection technique.