Peptide nucleic acid-based (PNA) array for the antigenic discrimination of canine parvovirus

A novel peptide nucleic acid (PNA)-based array was developed for use in ante-mortem antigenic typing discrimination in dogs with canine parvovirus (CPV). Cyclic benzothiazole-2-sulfonyl PNA monomers were synthesized that recognized GTA (CPV-2) and TAT (CPV-2a, -2b and -2c) at the nt 913–915 positions, and AAT (CPV-2 and CPV-2a), GAT (CPV-2b), and GAA (CPV-2c) at the nt 1276–1278 positions of the VP2 gene. The detection limits for aa 305 and aa 426 of the VP2 proteins belonging to the four CPV antigenic types were determined optically to be 40–2000 DNA copies, and the optimal cut-off fluorescence signaling value was fixed at 5000. The PNA array described here was developed from 135 field dog fecal specimens and had 89.8% (62/69) sensitivity and 90.4% (66/73) specificity compared with a real-time PCR using the TaqMan assay, a gold standard method. This CPV PNA array could be used together with MGB probe assays as an attractive novel tool for ante-mortem antigenic typing discrimination.