Construction and Immunogenicity of Recombinant Adenovirus for Expression of Neuraminidase of Influenza A(H1N1) Virus

Objective To construct a recombinant adenovirus for expression of neuraminidase(NA) of influenza A(H1N1) virus.Methods NA gene was amplified from plasmid pMD19T-simple-NA and cloned into shuttle plasmid pShuttleCMV,based on which a recombinant adenovirus plasmid was constructed by homologous recombination and transfected to Ad-293 cells to package recombinant adenovirus Ad-NA.The transcription and expression of NA gene in Vero cells were determined by RT-PCR and IFA.Recombinant adenovirus Ad-NA was purified by density gradient centrifugation with cesium chloride,with which mice were immunized and determined for NA antibody titer in sera by ELISA.Results Digestion of recombinant adenovirus plasmid with PacⅠ proved that the shuttle plasmid containing the target gene was integrated into the genome of adenovirus.NA gene was successfully transcribed and expressed in Vero cells.Recombinant adenovirus Ad-NA stimulated the secretion of NA antibody in mice.The antibody level 4 weeks after primary immunization reached a peak value of 1 ∶ 100 000.Conclusion The recombinant adenovirus for expression of NA of influenza A(H1N1) virus was successfully constructed,which induced effective immune response in mice.It laid a foundation of development of recombinant influenza A(H1N1) vaccine.