Modification of PCV-2 virulence by substitution of the genogroup motif of the capsid protein

Allemandou, Aude; Grasland, Béatrice; Hernandez-Nignol, Anne-Cécile; Kéranflec'h, André; Cariolet, Roland; Jestin, André

The parental and mutant DNA clones are infectious in vitro At 24 h post-transfection of PK15 cells, the capsid protein was detected by IPMA for the four constructions, confirming that both PCV-2 parental and mutant DNA clones were able to produce viral proteins (data not shown). The ability of parental and mutant clones to generate infectious virus was assessed by infecting fresh PK15 with the supernatants of these transfected cells. The cells infected with supernatants of both PCV-2 parental clones showed PCV-2 antigens in their nucleus ( Figures 1A and 1B) . Supernatants recovered from PK15 cells transfected with the mutant clones allowed the infection of fresh PK15 cells as evidenced by the IPMApositive cells (Figures 1C and 1D) . Thus, parental and capsid mutant clones were infectious in vitro and able to produce viral infectious particles.