West nile virus vaccine, and method for production thereof

Abstract

The invention provides virus-like particles (VLP) highly secreting or producing signal peptide obtained by altering a signal sequence derived from West Nile virus (WNV), the signal peptide, a WNV VLP secretion expression vector containing a nucleic acid encoding prM protein and E protein, a WNP VLP highly secreting or producing animal cell line harboring the vector, a WNV vaccine containing WNV VLP obtained by the cell line as an active ingredient, and a WNV DNA vaccine containing the VLP secretion expression vector as an active ingredient.

1 . An isolated nucleic acid substantially consisting of a base sequence encoding a signal peptide comprising an amino acid sequence the same or substantially the same as the amino acid sequence of
 (a) the amino acid sequence shown by SEQ ID NO: 1 or   (b) a partial amino acid sequence of the amino acid sequence of said (a) comprising at least the amino acid sequence shown by amino acid residues 11-25.   
     
     
         2 . A West Nile virus-like particle expression vector comprising a nucleic acid comprising a base sequence encoding
 (1) a signal peptide comprising an amino acid sequence the same or substantially the same as the amino acid sequence of
 (a) the amino acid sequence shown by SEQ ID NO: 1 or 
 (b) a partial amino acid sequence of the amino acid sequence of said (a) comprising at least the amino acid sequence shown by amino acid residues 11-25, and 
   (2) prM protein and E protein derived from West Nile virus.   
     
     
         3 . A transformant obtained by transformation with the vector of  claim 2 . 
     
     
         4 . A method of producing a West Nile virus-like particle, comprising culturing the transformant of  claim 3 , and recovering a virus-like particle secreted in a medium. 
     
     
         5 . A West Nile virus-like particle obtained by the method of  claim 4 . 
     
     
         6 . A West Nile virus vaccine comprising the particle of  claim 5  as an active ingredient. 
     
     
         7 . A West Nile virus vaccine comprising the vector of  claim 2  as an active ingredient. 
     
     
         8 . A method of preventing West Nile fever, comprising administering an effective amount of the vector of  claim 2  to a subject. 
     
     
         9 . A method of preventing West Nile fever, comprising administering an effective amount of the virus-like particles of  claim 5  to a subject.