Abstract: We constructed a recombinant plasmid and expressed the purified target protein, and used SDS-PAGE, Western blot and Native-PAGE to test protein. The multimers of the target protein were analyzed by Superdex^TM 200 gel chromatography, and the particle size of the target protein was analyzed by dynamic light scattering and transmission electron microscopy. The immune response of the protein was detected by enzymelinked immunosorbent assay with
 fourimmunized serum. The results show that plasmid pET26b-PP-3copy-Aβ1-6-loop123 was successfully constructed, and the target protein was
successfully expressed. There are three oligomers in the target protein, which are 24mer, 12mer and 2mer, and the particle size of the protein is about 20 nm, and has an immune response to the βamyloid protein.

Key words: Norovirus recombinant P particle, soluble expression; protein immunogenicity, protein vaccine