[Construction and rescue of infectious cDNA clone of pigeon-origin Newcastle disease virus strain JS/07/04/Pi].
Based on the complete genome sequence of pigeon-origin Newcastle disease virus strain JS/07/04/ Pi(genotype VIb), nine overlapped fragments covering its full-length genome were amplified by RT-PCR. The fragments were connected sequentially and then inserted into the transcription vector TVT7/R resulting in the TVT/071204 which contained the full genome of strain JS/07/04/Pi. The TVT/071204 was co-transfected with three helper plasmids pCI-NP, pCI-P and pCI-L into the BSR cells, and the transfected cells and culture supernatant were inoculated into 9-day-old SPF embryonated eggs 60 h post-transfection. The HA and HI tests were conducted following the death of embryonated eggs. The results showed that the allantoic fluids obtained were HA positive and the HA could be inhibited by anti-NDV serum which indicated that the strain JS/07/04/Pi was rescued successfully. The rescued virus rNDV/071204 showed similar growth kinetics to its parental virus in CEF. The successful recovery of this strain would contribute to the understanding of the host-specificity of pigeon-origin NDV and to the development of the novel vaccines against the NDV infection in pigeons.