Cold-adapted Rescue Of H1N1 Subtype Influenza Virus From Eight Plasmids System

Recently, the reverse genetics provided a favourable opportumity for live attenuated vaccines.Efforos are currently under way to develop a live attenuated influenza vaccines which based on reverse genetics. In this dissertation,we used the eight-plasmid rescue system and slected 6 internal gene of influenza A strain A/Ann Arbor/6/60(H2N2)as the genetic backbone for generation of recormbinants H1N1 subtype influenza virus and expressing the HA and NA from 2006～2007 cirulating strain A/New Caledonia/20/99(H1N1).Finally, we successfully established a cold-adapted H1N1 subtype influenza virus rescue system.This study is strategically important for vaccine development and influenza prevention. First, HA and NA gene fragments of Influenza virus that prevailed from 2006 to 2007 were amplified by RT-PCR. We successful construct the two-way transcription/expression plasmids which are pAD-PB2,pAD-PB1,pADF-PA,pAD-NP,pAD-M,pAD-NS and pAD-HA,pAD-NA, and those plasmids are cold-adapted rescued by A/New Caledonia /20/99(H1N1) 8 plasmid system. Second, an A/New Caledonia/20/99(H1N1) Influenza virus's cold-adapted strain was gained with using the eight plasmids system and the availability of the cold-adapted system was checked, so we built a reverse genetic technology frame to rescue virus with those cold-adapted strain. This technology can make the Influenza virus more pure and more optimize to the transfection system.The successful rescue of H1N1 subtype Influenza is strategically important for manufacture a live vaccine,but whether this Influenza virus strain can become a vaccine strain or not ,It's still need to be verified and tested.