tailieunhanh - Báo cáo sinh học: " Open Access Cloning of the canine RNA polymerase I promoter and establishment of reverse genetics for influenza A and B in MDCK cells"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Cloning of the canine RNA polymerase I promoter and establishment of reverse genetics for influenza A and B in MDCK cells | Virology Journal BioMed Central Open Access Methodology Cloning of the canine RNA polymerase I promoter and establishment of reverse genetics for influenza A and B in MDCK cells Zhaoti Wang and Gregory M Duke Address Medlmmune 297 North Bernardo Avenue Mountain View CA 94043 USA Email Zhaoti Wang - wangz@ Gregory M Duke - dukeg@ Corresponding author Published 23 October 2007 Received 13 September 2007 Accepted 23 October 2007 Virology Journal 2007 4 102 doi l743-422X-4-l02 This article is available from http content 4 l l02 2007 Wang and Duke licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background Recent incidents where highly pathogenic influenza A H5Nl viruses have spread from avian species into humans have prompted the development of cell-based production of influenza vaccines as an alternative to or replacement of current egg-based production. Madin-Darby canine kidney MDCK cells are the primary cell-substrate candidate for influenza virus production but an efficient system for the direct rescue of influenza virus from cloned influenza cDNAs in MDCK cells did not exist. The objective of this study was to develop a highly efficient method for direct rescue of influenza virus in MDCK cells. Results The eight-plasmid DNA transfection system for the rescue of influenza virus from cloned influenza cDNAs was adapted such that virus can be generated directly from MDCK cells. This was accomplished by cloning the canine RNA polymerase I pol I promoter from MDCK cells and exchanging it for the human RNA pol I promoter in the eight plasmid rescue system. The adapted system retains bi-directional transcription of the viral cDNA template into both RNA pol I transcribed