Expression And Purification Of Influenza A Virus M2 Protein And Detection Of Its Antigenicity

Influenza is one of the most prevalent viral diseases in humans. One of the most hotly pursued strategies for a universal vaccine against influenza A is based on a flu protein called M2. This protein forms an ion channel crossing the membrane of a virus particle or infected cell, barely jutting out from the surface. M2 seems to be a good candidate antigen for a vaccine because of its high degree of conservation since the emergence of the highly virulent pandemic strain of 1918. However, natural M2 target antigen presents few copies in the virus particles, it is hard to induce broad immune response by present vaccines.In this study, we obtained occasionally an entire length M2 mutant protein, with high expression in protokaryon expression system. We reconstructed the fused protein and named it as M2MH. Followed by separation and purification, after a series of condition optimization, we have got the high-purity protein.we generated antiserum from BALB/C mice following immunization with purified protein. The antiserum showed strong binding to M2 transfected 293T cell and to virus infected MDCK cells. It is also displayed high binding to the majority of M2e variants from natural viral isolates, including highly pathogenic avian strains, which were recently reported to infect humans, suggested that the purified protein was a good immunogenicity. In the virus challenge assay, immunized mice showed higher survival rate than control, which indicated that purified protein could confer immune protection. These results suggest the potential of the purified full-length M2 protein as a broad-spectrum effective vaccine to suppress proliferations of multiple subtypes of Influenza A Virus。we characterized several hybridoma cell lines with the stable secretion of M2 specific monoclonal antibodies (MAbs), lays a good foundation to perform further studies on diagnosis, therapy and mechanism for infections of influenza A virus.