Development of a T7 RNA polymerase expressing cell line using lentivirus vectors for the recovery of recombinant Newcastle disease virus

The development of a T7 RNA polymerase (T7 RNAP) expressing cell line i.e. BSR T7/5 cells marks an improvement reverse genetics for the recovery recombinant Newcastle disease virus (rNDV). is developed by transient transfection plasmid encoding RNAP gene rNDV rescue. However, expression decreases gradually over multiple passages and eventually hinders rescue rNDV. To address this issue, lentiviral vector was used to develop RNAP-expressing HEK293-TA (HEK293-TA-Lv-T7) SW620 (SW620-Lv-T7) lines, evidenced after subsequent 20 passages. rescued successfully using HEK293-TA-Lv-T7 clones (R1D3, R1D8, R5B9) SW620-Lv-T7 (R1C11, R3C5) transfection, yielding comparable efficiency titres that T7/5. This study provides new tools insights into virology genetics.