Methods of diagnosing als

Abstract

The invention relates to an epitope protection assay for use in diagnosis, prognosis and therapeutic intervention in diseases, for example, involving polypeptide aggregation, such as prion infections. The methods of the invention first block accessible polypeptide target epitope with a blocking agent. After denaturation of the polypeptide, a detecting agent is used to detect protein with target epitope that was inaccessible during contact with the blocking agent. The invention also relates to novel amyotrophic lateral sclerosis-specific epitopes and their uses to make antibodies, and to the novel antibodies and uses thereof.

We claim: 
     
         1 . A method of detecting or diagnosing amyotrophic lateral sclerosis in a subject comprising the steps of:
 (a) contacting a test sample of said subject with an antibody specific for an ALS-specific epitope, wherein the ALS-specific epitope is selected from the group consisting of:   
       
         
           
                 
                 
               
                     
                   DLGKGGNEESTKTGNAGS; 
                 
                     
                   and 
                 
                     
                     
                 
                     
                   NPLSRKHGGPKDEE 
                 
             
                
                
                
                
               
            
           
         
         
           to produce an antibody-antigen complex; 
         
         (b) measuring the amount of the antibody-antigen complex in the test sample; and 
         (c) comparing the amount of antibody-antigen complex in the test sample to a control;
 wherein a difference in the amount of antibody-antigen complex in the test sample as compared to the control is indicative of amyotrophic lateral sclerosis. 
 
       
     
     
         2 . The method of  claim 1 , wherein the antibody is specific for DLGKGGNEESTKTGNAGS. 
     
     
         3 . The method of  claim 1 , wherein the antibody is specific for NPLSRKHGGPKDEE. 
     
     
         4 . The method according to  claim 1 , wherein the antibody is monoclonal, polyclonal, chimeric or humanized. 
     
     
         5 . The method according to  claim 1 , wherein the antibody is an antibody fragment. 
     
     
         6 . The method according to  claim 5 , wherein the antibody fragment is a Fab, Fab′, F(ab′) 2 , scFv, dsFv, ds-scFv, dimers, minibodies, diabodies, or multimers thereof or bispecific antibody fragments. 
     
     
         7 . A kit for diagnosing amyotrophic lateral sclerosis according to the method of  claim 1  comprising an antibody specific for an ALS-specific epitope, wherein the ALS-specific epitope comprises an isolated peptide selected from the group consisting of: 
       
         
           
                 
                 
               
                     
                   DLGKGGNEESTKTGNAGS; 
                 
                     
                   and 
                 
                     
                     
                 
                     
                   NPLSRKHGGPKDEE; 
                 
             
                
                
                
                
               
            
           
         
         and instructions for the use thereof. 
       
     
     
         8 . The kit according to  claim 7 , wherein the antibody is specific for DLGKGGNEESTKTGNAGS. 
     
     
         9 . The kit according to  claim 7 , wherein the antibody is specific for NPLSRKHGGPKDEE. 
     
     
         10 . The kit of  claim 7  further comprising a recombinant peptide standard. 
     
     
         11 . The kit of  claim 10  wherein the standard is an isolated peptide selected from the group consisting of: 
       
         
           
                 
                 
               
                     
                   DLGKGGNEESTKTGNAGS; 
                 
                     
                   and 
                 
                     
                     
                 
                     
                   NPLSRKHGGPKDEE. 
                 
             
                
                
                
                
               
            
           
         
       
     
     
         12 . A diagnostic agent comprising (1) an antibody specific for an ALS-specific epitope, wherein the ALS-specific epitope comprises an isolated peptide selected from the group consisting of: 
       
         
           
                 
                 
               
                     
                   DLGKGGNEESTKTGNAGS; 
                 
                     
                   and 
                 
                     
                     
                 
                     
                   NPLSRKHGGPKDEE; 
                 
             
                
                
                
                
               
            
           
         
         attached to (2) a label that produces a detectable signal, directly or indirectly. 
       
     
     
         13 . A diagnostic according to  claim 12 , wherein the antibody is specific for DLGKGGNEESTKTGNAGS. 
     
     
         14 . A diagnostic according to  claim 12 , wherein the antibody is specific for NPLSRKHGGPKDEE. 
     
     
         15 . The diagnostic agent of  claim 12 , wherein the label comprises a radioisotype, a fluorescent compound, a chemiluminescent compound, an enzyme, an imaging agent or a metal ion. 
     
     
         16 . A kit comprising the diagnostic agent of  claim 12  and instructions for the use thereof.