Protecting pigs from simultaneous infection with avian, swine, and human influenza viruses would be an effective strategy to prevent the emergence of reassortants with pandemic potential. M2 protein is a candidate antigen for so-called 'universal vaccines' that confer cross-protection from different influenza viruses in a strain- and subtype-independent manner. We tested whether a recombinant F gene-deleted Sendai virus vector, which contained an M2 gene derived from an H5N1 avian influenza virus (SeV/ΔF/H5N1M2), could induce a cross-reactive antibody response to the extracellular domain of M2 protein (M2e) in pigs. SeV/ΔF/H5N1M2 induced an antibody response to M2e when the vector was inoculated intramuscularly. The antibodies induced by SeV/ΔF/H5N1M2 cross-reacted with M2e derived from different avian, swine, and human influenza viruses. In mice, however, SeV/ΔF/H5N1M2 did not confer cross-protection from challenge with a heterologous H3N2 influenza virus. Our results confirm those of other studies that indicated that antibodies to M2e do not mediate protection to influenza viruses in pigs. br />(Viral Disease and Epidemiology Research Division)
References:
Hikono H. et al. (2012) Vet. Immunol. Immunopathol. 146(1):92-96