title: [Establishment of a stable and inducible mammalian cell line expressing influenza virus A M2 protein].
abstract: Matrix protein 2(M2) is an integral tetrameric membrane protein of influenza A virus, which functions as ion channel. M2 sequence has shown remarkable conservation, so there has been growing interest in it as "universal" vaccine. In order to establish a stable 293 cell line that express M2 protein under the control of the tetracycline operator, M2 gene was obtained by PCR amplification from the plasmid containing the segment 7 of influenza A virus strain A/PR/8/34 firstly. The PCR product was cloned into BamH I/Not I restriction site of pcDNA5/FRT/TO vector, and cotransfected with pOG44 which express Flp recombinase into Flp-In T-REx-293 cell. Integration of pcDNA5/FRT/TO-M2 into the cell genome at the Flp Recombination Target (FRT) site brought the SV40 promoter and the initiation codon in frame with the hygromycin resistance gene. Thus, stable cell lines were selected for hygromycin resistance. The expression of M2 protein from hygromycin-resistant cell was induced by addition of tetracycline into the cell culture media, and then tested by indirect immunofluorescence assay (IFA). 16 strains with high expression of M2 were selected. After subculturing for more than ten passages, the cell lines still stably expressed M2 protein. No M2 protein could be detected without tetracycline induction, suggesting that the expression was strictly controlled by tetracycline operator. The cell lines expressing M2 will be useful for further functional studies of M2 protein, detection of immune response against natural structure M2 protein and development of live attenuated influenza virus vaccine with reverse genetics technique.
authors.affiliation: State Key Laboratory for Molecular Virology and Genetic Engineering, Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Liu
authors.forename: Jianqiang
authors.initials: J
authors.lastname: Guo
authors.forename: Lihong
authors.initials: L
authors.lastname: Yao
authors.forename: Aijun
authors.initials: A
authors.lastname: Chen
authors.forename: Jinqi
authors.initials: J
authors.lastname: Fu
authors.forename: Zhiqing
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D015870:Gene Expression; D005822:Genetic Vectors / Q000235:genetics*; D057809:HEK293 Cells; D006801:Humans; D009980:Influenza A virus / Q000235:genetics / Q000378:metabolism; D007252:Influenza Vaccines / Q000235:genetics; D009875:Operator Regions, Genetic; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D013752:Tetracycline / Q000494:pharmacology; D014162:Transfection; D014763:Viral Matrix Proteins / Q000096:biosynthesis* / Q000235:genetics; D000086082:Viroporin Proteins
chemical_list: D007252:Influenza Vaccines; D011994:Recombinant Proteins; D013752:Tetracycline; D014763:Viral Matrix Proteins; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins