Plasmids carrying the HA, NA, NP, M1, and M2 genes, respectively, of the avian influenza virus (AIV) A/Chicken/Henan/12/2004(H5N1) strain were administered to mice, and the mice were challenged with the homologous virus later. The mice immunized with M1 plasmid survived 25% with five immunizations. The mixture of M1 and NP plasmids protected 95% of the mice against the homologous virus, and 80% of the mice against a challenge with heterologous H1N1 (PR8) virus (Chen et al., 2009).
Chen et al., 2009: Chen Q, Kuang H, Wang H, Fang F, Yang Z, Zhang Z, Zhang X, Chen Z. Comparing the ability of a series of viral protein-expressing plasmid DNAs to protect against H5N1 influenza virus. Virus genes. 2009; 38(1); 30-38. [PubMed: 19067149].