Polypeptide serving as immune stimulus of B-cell epitope or peptide hapten for forming polypeptide immunogen and application of polypeptide

The invention provides a polypeptide containing a T helper cell epitop (Th epitope), which can serve as an immune stimulus of a B-cell epitope or a peptide hapten for forming a polypeptide immunogen,and application of polypeptide. The B-cell epitope or the peptide hapten is covalently connected with polypeptide through a connecting peptide to form the polypeptide immunogen; the polypeptide-containing polypeptide immunogen is obtained through repeated screening and analyzing of mice, so that the immunogenicity of the B-cell epitope or the peptide hapten can be enhanced remarkably, an antibodywhich can be specifically bonded to a target antigen protein can be produced, the immunoregulation of biased Th2 can be enhanced remarkably, and symptoms can be improved. The polypeptide as well as polypeptide-containing immunogen, derivatives and analogues provided by the invention can also be used for recombinant microorganisms and animals or plants and cells which can be genetically modified, so that the recombinant mic