Production and characterization of monoclonal antibodies against nucleoprotein of avian influenza virus.

The present study was carried out with an aim to develop anti-nucleoprotein (anti-NP) monoclonal antibodies (MAbs) for use in immunodiagnostic testing for detection of avian influenza virus (AIV) antigen or antibodies. The NP gene of AIV, cloned in pET vector, was expressed in Escherichia coli BL 21 strain to produce a 6x-His tagged recombinant NP (rNP) antigen of ∼61 kDa molecular weight as soluble fraction. The rNP antigen was detected in soluble fraction of bacterial cell lysate with anti-His HRPO conjugate and reacted with the reference AIV antibody positive serum in immunoblotting.