Provide the polypeptide no more than 100 amino acid, which polypeptide includes one or more sequences, it is identical in the SEQ ID 1-6 of pass any one at least 60%, it or include two or more epitopes with 7 amino acid or more, each epitope, it has at least 60% identical, has with epitope an any one subsequence in the SEQ ID 1-6 of identical length:Wherein, polypeptide is immunogenic in the vertebrate for indicating a kind of major histocompatibility complex (MHC) allele, and wherein polypeptide is not a complete influenza virus protein matter.
