Development of the cell-ELISA test for the subtype identification of circulating influenza A(H1) and A(H3) viruses

The sensitive version of cell-ELISA was developed for the subtype-specific differentiation of current influenza A(H1N1)pdm09 and A(H3N2) viruses that are circulating in the human population. This method is based on the estimation of virus reproduction in infected MDCK cells. The detection step of this method is an interaction of the subtype-specific monoclonal antibodies (mAbs) with the viral hemagglutinin (НА) molecule. The influenza A virus strains, isolated in the 2014 epidemic season, were used to validate this method. It was shown that when using mAbs # 1/ # 2 or # 4 at a concentration of 10-15 μg/ml, the developed variant of cell-ELISA was able to detect НА protein synthesized in the infected cells of influenza A(H3N2) and A(H1N1)pdm09 viruses, respectively. The developed method can be used for the identification of modern influenza A viruses with low hemagglutination activity, which is not possible by the conventional hemagglutination inhibition test