Production and Characterization of Monoclonal Antibodies Against NS1 Protein of H5N1 Avian Influenza Virus

A panel of 11 murine monoclonal antibodies (MAbs) was generated against NS1 (non-structural) protein of highly pathogenic avian influenza H5N1 virus using whole viral antigen as immunogen and as antigen in the preliminary screening of clones followed by a more specific screening through recombinant NS1 protein-based ELISA. Isotyping showed two clones 10E2 (IgG2b) and 5H8 (IgG3) to be IgG type and 6B9 and 4C4 to be IgA type, while the rest could not be isotyped due to weak reactivity with NS1 antigen. The subclone 10E2E7G3 was selected for subsequent work, which showed comparatively higher OD in NS1-based ELISA. The reactivity of 10E2E7G3 with H5N1 virus as well as recombinant NS1 protein was confirmed in Western blot analysis. The anti-NS1 MAbs produced in the present work may be valuable in developing an immunodiagnostic assay as a DIVA test for differentiating infected from vaccinated birds in AIV.