Cowpea Mosaic Virus Chimeric Particles Bearing the Ectodomain of Matrix Protein 2 (M2E) of the Influenza A Virus: Production and Characterization

摘要

The epitope presentation system for the ectodomain of the M2 protein (M2e) of the influenza A virus was constructed on the basis of the cowpea mosaic virus (CPMV) for expression in the plant Vigna unguiculata. CPMV is widely used as a vector to produce immunogenic chimeric virus particles (CVPs) bearing epitopes of various infectious human and animal pathogens. To produce chimeric CPMV particles in plants, two binary vectors were constructed to bear a modified gene coding for the CPMV S-coat protein with insertions of M2e epitopes of human influenza and bird influenza viruses. Antigenic and immunogenic properties of CVPs were investigated in mice immunization experiments. CVPs were shown to induce anti-M2e IgG production and to partly protect mice against a challenge with low doses of the influenza virus. However, low infec-tivity and immunogenicity of chimeric CPMV particles indicate that the plant virus-based systems for M2e epitope presentation requires further optimization in order to use plants as a possible source of flu vaccines.