Recombinant influenza virus proteins, including influenza capsomers, subviralparticles, virus-like particles (VLP), VLP complexes, and/or any portions ofthereof, are provided as a vaccine for influenza viruses. The invention isbased on the combination of two vaccine technologies: (1) intrinsically saferecombinant vaccine technology, and (2) highly immunogenic, self-assembledprotein macromolecules embedded in plasma membranes and comprised of multiplecopies of influenza virus structural proteins exhibiting neutralizing epitopesin native conformations. More specifically, this invention relates to thedesign and production of functional homotypic and heterotypic recombinantinfluenza virus-like particles (VLPs) comprised of recombinant structuralproteins of human influenza virus type A/Sydney/5/94 (H3N2) and/or avianinfluenza virus type A/Hong Kong/1073/99 (H9N2) in baculovirus-infected insectcells and their application as a vaccine in the prevention of influenzainfections and as a laboratory reagent for virus structural studies andclinical diagnostics.
