Tumor antigen proteins, genes therefor, and tumor antigen peptides

Abstract

DNA encoding a protein having the amino acid sequence shown in SEQ ID NO: 2 or a variant protein thereof in which one or more amino acid residues are substituted, deleted or added, said protein or variant protein thereof being capable of yielding, through its intracellular decomposition, peptide fragment(s) which can bind to major histocompatibility complex (MHC) class I antigen and which can be recognized by T cells in such binding state, medicines comprising said DNA as an active ingredient, expression plasmids comprising said DNA, transformants transformed with said expression plasmids, as well as tumor antigen proteins and tumor antigen peptides produced by expression of said DNA.

1 . An isolated polynucleotide comprising a nucleotide sequence selected from the group consisting of: 
 (a) the nucleotide sequence of SEQ ID NO:1; and    (b) a nucleotide sequence encoding the amino acid sequence of SEQ ID NO:2,    wherein said polynucleotide encodes a protein which yields, through intracellular decomposition, peptide fragment(s) which bind(s) to major histocompatibility complex (MHC) class I antigen and is recognized by tumor-specific cytotoxic T lymphocytes (CTLs) in such binding state.    
     
     
         2 . An isolated polynucleotide comprising a nucleotide sequence encoding a peptide that is a peptide fragment of a protein selected from the group consisting of: 
 (a) a protein comprising an amino acid sequence shown in SEQ ID NO:2; and    (b) a protein encoded by a DNA comprising a nucleotide sequence shown in SEQ ID NO:1,    wherein said peptide comprises the amino acid sequence of positions 749-757, 736-744, 785-793, or 690-698 in the amino acid sequence of SEQ ID NO:2, and binds to MHC class I antigen and is recognized by tumor-specific CTLs when bound to MHC class I antigen.    
     
     
         3 . An expression plasmid comprising the polynucleotide of  claim 1  or  2 .  
     
     
         4 . A host cell comprising the expression plasmid of  claim 3 .  
     
     
         5 . A composition comprising, as an active ingredient, the polynucleotide of  claim 1  or  2 .  
     
     
         6 . A composition comprising, as an active ingredient, the expression plasmid of  claim 3.