Detection of canine parvovirus DNA in paraffin-embedded tissues by polymerase chain reaction

Canine Parvovirus (CPV) is seemingly a 'new' virus which suddenly appeared during the mid-1970's in an epizootic of disease in dogs. The virus is very similar to the feline panleukopenia virus (FPV), and recent studies have underlined the possible emergence of CPV as a variant of a virus from some other carnivore--possibly from FPV (Parrish, 1990). Several conserved amino-acid changes between CPV and FPV isolates have been defined by cloning and sequencing the capsid-protein gene. An alternative to cloning and sequencing the entire capsid-protein gene would be to use PCR amplification of short regions of the gene containing the appropriate variable amino-acid codons. In addition, use of PCR would also facilitate the study of virus samples which cannot be recovered as infectious agents, e.g. after having undergone formalaldehyde fixation and paraffin-embedding procedures. This study reports on the amplification of CPV DNA from 15-year-old tissue sections which have been prepared by formaldehyde or paraformaldehyde-lysine-periodate-glutaraldehyde fixation, using PCR with various primer pairs within the capsid-protein gene of CPV.