Avian influenza virus (AIV) is a highly variable pathogen. The M2 gene of AIV is a transmembrane protein. It has highly conservative antigenic epitopes and is a potential antigen for cross-protection. In this study, the recombinants containing the full-length M2 and the transmembrane segment deleted M2 were constructed respectively. When measuring the expression of the two constructs, we found that the full-length M2 failed to express in the prokaryotic expression system, whereas transmembrane segment deleted M2 was highly expressed as fusion protein in a soluble form. The fusion protein reacted with SPF chicken serum specific for AIV A/goose / Guangdong /1996(H5N1). The protein was purified by GST purification system and the purified protein was used to prepare anti-M2 serum in mice. Immunofluorescence test demonstrated the binding of the antiserum with AIV (H5N1) infected MDCK cells. The results suggest that the recombinant transmembrane segment deleted M2 could provide good antigenicity.
