Generation And Preliminary Characterization Of Chimeric Antibodies Against Neuraminidase Of H7N9 Subtype Influenza A Virus

Objective:To prepare the chimeric antibodies against neuraminidase?NA?of H7N9and to identify their functional properties,which provides a theoretical basis for the prevention and control of H7N9.Methods:Based on the original information of murine anti-N9 MAb,8 hybridoma cell lines specifically against influenza virus A/Anhui/1/2013?H7N9?NA were selected and genetically engineered to humanize.The chimeric antibodies were purified and their functions were investigated by ELISA,BLI,FACS,HI,NI,microneutralization,ADCC,Plaque assay and Competition ELISA.Results:The chimeric antibodies,1E2,3E3 and 5D1 against neuraminidase?NA?of H7N9 were obtained.The EC₅₀ of AH-N9 protein were 0.048?g/ml,0.028?g/ml and 0.675?g/ml,respectively.1E2 and 3E3 recognized similar antigenic epitopes and are different from 5D1 antigen recognition epitope.Three chimeric antibodies could prevent the infection of N9 subtype influenza virus as well as the NAI-resistant mutants.1E2 and 3E3 could prevent the infectivity with H7N9 and H11N9 virus and reduce their size of viral plaque.Conclusions Three chimeric antibodies specific to N9 could prevent the infection of N9 subtype influenza virus as well as the NAI-resistant mutants and could be used for prevention and treatment of H7N9 avian influenza and provide a a certain theoretical basis for antibody drugs.