Method for measuring anti-wt1 antibody

Abstract

Provided is an invention relating to a method for measuring an anti-WT1 antibody in a sample allowing measurement and evaluation of the anti-WT1 antibody with higher accuracy and to use of the method. The method for measuring an anti-WT1 antibody in a sample includes using a polypeptide having antigenicity to the anti-WT1 antibody selected from a polypeptide comprising the amino acid sequence of positions 294-449 in SEQ ID NO: 1, a partial polypeptide of the polypeptide, and a polypeptide including an amino acid sequence having deletion, substitution, or addition of one to several amino acids in the amino acid sequence constituting each of these polypeptides and/or a polypeptide having antigenicity to the anti-WT1 antibody selected from a polypeptide comprising the amino acid sequence of positions 181-324 in SEQ ID NO: 1, a partial polypeptide of the polypeptide, and a polypeptide including an amino acid sequence having deletion, substitution, or addition of one to several amino acids in the amino acid sequence constituting each of these polypeptides.

1 . A method for measuring an anti-WT1 antibody in a sample, the method comprising:
 contacting a sample with at least one polypeptide having antigenicity to the anti-WT1 antibody selected from the group consisting of
 i) a polypeptide consisting of an amino acid sequence of positions 181-324 in SEQ ID NO: 1, and 
   ii) a polypeptide consisting of an amino acid sequence where the amino acid sequence of i) the polypeptide has been subjected to at least one of deletion, substitution, and addition of 1 to 5 amino acids; and   measuring a concentration of the anti-WT1 antibody in the sample.   
     
     
         2 . The method according to  claim 1 , wherein the contacting comprises immobilizing at least one of i) the polypeptide and ii) the polypeptide to a solid phase and contacting at least one immobilized polypeptide with the sample, and the measuring comprises detecting a reaction product between at least one immobilized polypeptide and an anti-WT1 antibody present in the sample to measure a concentration of the anti-WT1 antibody. 
     
     
         3 . A method for diagnosing a WT1-associated disease, comprising:
 contacting a sample from a subject with at least one polypeptide having antigenicity to an anti-WT1 antibody selected from the group consisting of
 i) a polypeptide consisting of an amino acid sequence of positions 181-324 in SEQ ID NO: 1, and 
 ii) a polypeptide consisting of an amino acid sequence where the amino acid sequence of i) the polypeptide has been subjected to at least one of deletion, substitution, and addition of 1 to 5 amino acids; and 
   detecting the anti-WT1 antibody in the subject.   
     
     
         4 . The method according to  claim 3 , wherein the WT1-associated disease is leukemia. 
     
     
         5 . A method for predicting a responder to or for therapeutic monitoring of WT1 vaccine therapy of cancer, comprising:
 contacting a sample from a subject with at least one polypeptide having antigenicity to an anti-WT1 antibody selected from the group consisting of
 i) a polypeptide consisting of an amino acid sequence of positions 181-324 in SEQ ID NO: 1, and 
 ii) a polypeptide consisting of an amino acid sequence where the amino acid sequence of i) the polypeptide has been subjected to at least one of deletion, substitution, and addition of 1 to 5 amino acids; and 
   detecting the anti-WT1 antibody in the subject.   
     
     
         6 . The method according to  claim 5 , wherein the cancer is brain tumor or colon cancer. 
     
     
         7 . A composition, comprising:
 at least one polypeptide having antigenicity to the anti-WT1 antibody selected from the group consisting of   i) a polypeptide consisting of an amino acid sequence of positions 181-324 in SEQ ID NO: 1, and   ii) a polypeptide consisting of an amino acid sequence where the amino acid sequence of i) the polypeptide has been subjected to at least one of deletion, substitution, and addition of 1 to 5 amino acids.   
     
     
         8 . The composition according to  claim 7 , wherein i) the polypeptide is included. 
     
     
         9 . A method for detecting an autoantibody, comprising:
 modifying a WT1 protein such that a modified WT1 protein has a surface where an epitope site of a polypeptide is exposed; and   contacting a sample from a subject with the modified WT1 protein such that an autoantibody that recognizes the modified WT1 as an antigen is detected,   wherein the polypeptide comprises at least one selected from the group consisting of   i) a polypeptide consisting of an amino acid sequence of positions 181-324 in SEQ ID NO: 1, and   ii) a polypeptide consisting of an amino acid sequence where the amino acid sequence of i) the polypeptide has been subjected to at least one of deletion, substitution, and addition of 1 to 5 amino acids.   
     
     
         10 . The method according to  claim 1 , wherein the measuring of the concentration of the anti-WT1 antibody comprises performing one of radioimmunoassay, enzyme immunoassay, fluoroimmunoassay, indirect fluorescence assay, luminescent immunoassay, physicochemical assay, and Western blotting. 
     
     
         11 . The method according to  claim 1 , wherein the measuring of the concentration of the anti-WT1 antibody comprises performing ELISA. 
     
     
         12 . The method according to  claim 1 , wherein the contacting comprises contacting the sample with i) the polypeptide consisting of the amino acid sequence of positions 181-324 in SEQ ID NO: 1. 
     
     
         13 . The method according to  claim 12 , wherein the contacting comprises immobilizing i) the polypeptide to a solid phase to obtain an immobilized polypeptide and contacting the sample with the immobilized polypeptide, and the measuring comprises detecting a reaction product between the immobilized polypeptide and an anti-WT1 antibody present in the sample to measure a concentration of the anti-WT1 antibody. 
     
     
         14 . The method according to  claim 12 , wherein the measuring of the concentration of the anti-WT1 antibody comprises performing one of radioimmunoassay, enzyme immunoassay, fluoroimmunoassay, indirect fluorescence assay, luminescent immunoassay, physicochemical assay, and Western blotting. 
     
     
         15 . The method according to  claim 12 , wherein the measuring of the concentration of the anti-WT1 antibody comprises performing ELISA. 
     
     
         16 . The method according to  claim 3 , wherein the contacting comprises contacting the sample with i) the polypeptide consisting of the amino acid sequence of positions 181-324 in SEQ ID NO: 1. 
     
     
         17 . The method according to  claim 16 , wherein the WT1-associated disease is leukemia. 
     
     
         18 . The method according to  claim 3 , further comprising:
 determining the subject's immune response ability based on whether the anti-WT1 antibody is detected in the subject.   
     
     
         19 . The method according to  claim 16 , further comprising:
 determining the subject's immune response ability based on whether the anti-WT1 antibody is detected in the subject.   
     
     
         20 . The method according to  claim 17 , further comprising:
 determining the subject's immune response ability based on whether the anti-WT1 antibody is detected in the subject.