Detecting the Presence of Pyruvate Kinase Isoenzyme in Feces

Abstract

In order to selectively, qualitatively or/and quantitatively detect the pyruvate kinase isoenzyme of the tumor M2-PK type (tumor M2-PK) which serves as a tumor marker in human and animal feces to detect a malignant process in the gastrointestinal tract, tumor M2-PK is detected in a stool specimen by an immunoassay technique with the aid of at least one antibody which specifically binds tumor M2-PK and does not cross-react with any other pyruvate kinase isoenzyme. A test kit for diagnosing malignant tumor growth in the gastrointestinal tract and in particular in the intestines contains at least one receptor for tumor M2-PK which does not cross-react with any other pyruvate kinase isoenzyme and optionally contains additional reagents that are necessary for carrying out an immunoassay.

1 . A method for the detection of a malignant process in the gastrointestinal: tract of a human or animal, comprising
 obtaining a stool specimen, and   detecting any pyruvate kinase isoenzyme fragment of the tumor M2-PK type in said stool specimen as an indication of a malignant process in the gastrointestinal tract of said human or animal.   
     
     
         2 . The method according to  claim 1 , wherein the pyruvate kinase isoenzyme fragment of the tumor M2-PK type is detected immunochemically by contacting said stool specimen with at least one receptor which binds to a pyruvate kinase isoenzyme of the tumor M2-PK type and detecting any receptor bound to pyruvate kinase isoenzyme of the tumor M2-PK type. 
     
     
         3 . The method according to  claim 1 , wherein said receptor is an anti-pyruvate kinase isoenzyme antibody. 
     
     
         4 . The method according to  claim 1 , wherein said receptor is a pyruvate kinase isoenzyme specific aptamer. 
     
     
         5 . The method according to  claim 1 , wherein said receptor is a monoclonal or polyclonal antibody which does not cross-react with constituents of human or animal feces other than pyruvate kinase isoenzyme of the tumor M2-PK type. 
     
     
         6 . The method according to  claim 1 , wherein said stool specimen is contacted with at least two different receptors, wherein a first receptor R1 is present in a solid phase and binds to a pyruvate kinase isoenzyme of the tumor M2-PK type, and at least one second receptor R2 is present in a liquid phase and binds to a pyruvate kinase isoenzyme of the tumor M2-PK type and carries a label or mediates binding to a detectable molecule,
 further comprising separating said solid phase from said liquid phase, and determining any label or detectable molecule.   
     
     
         7 . The method according to  claim 6 , wherein at least one of said receptors is an antibody. 
     
     
         8 . The method as claimed in  claim 7 , wherein an antibody which specifically binds to pyruvate kinase isoenzyme of the tumor M2-PK type is used as first receptor R1 bound to a solid phase, and a second antibody which binds to pyruvate kinase isoenzyme of the tumor M2-PK type is used as soluble receptor R2. 
     
     
         9 . The method according to  claim 1 , wherein said pyruvate kinase isoenzyme of the tumor M2-PK type is detected using ELISA, oscillating quartz crystals, microbalance, lateral flow, candelaber, TRACE or electrochemoluminescence technology. 
     
     
         10 . The method according to  claim 1 , wherein at least one antibody which specifically binds pyruvate kinase isoenzyme of the tumor M2-PK type and does not cross-react with any other pyruvate kinase isoenzyme is used in an immunoassay technique for said detection. 
     
     
         11 . The method as claimed in  claim 7 , wherein said antibody is a monoclonal antibody which is obtainable from the hybridoma cell line clone 1 (No. DSM ACC 2155), or an antibody which has the same specificity and selectivity. 
     
     
         12 . The method as claimed in  claim 6 , further comprising quantifying the amount of pyruvate kinase isoenzyme of the tumor M2-PK type present in the sample, wherein receptor R2 carries a label or mediates binding to a detectable molecule, the label or the detectable molecule in the solid phase is determined, and wherein at least one of the receptors R1 or R2 is an antibody which can specifically bind to pyruvate kinase isoenzyme of the tumor M2-PK type and discriminate between other pyruvate kinase isoenzymes. 
     
     
         13 . The method as claimed in  claim 12 , wherein receptor R1 is an antibody which specifically binds to pyruvate kinase isoenzyme of the tumor M2-PK type and discriminates between other pyruvate kinase isoenzymes. 
     
     
         14 . The method as claimed in  claim 13 , wherein receptor R2 is an antibody which carries a label. 
     
     
         15 . The method as claimed in  claim 13 , wherein receptor R2 is an enzyme-bound antibody and the method is carried out as an ELISA. 
     
     
         16 . The method according to  claim 6 , wherein said pyruvate kinase isoenzyme of the tumor M2-PK type is detected selectively, quantitatively or qualitatively as an indication of said malignant process. 
     
     
         17 . A method for the qualitative and/or quantitative detection of tumor M2-PK pyruvate kinase isoenzyme as an indication of the presence of a malignant process, comprising
 obtaining a test kit comprising at least one receptor for tumor M2-PK pyruvate kinase isoenzyme which does not cross-react with any other pyruvate kinase isoenzyme,   obtaining a stool specimen,   contacting said stool specimen with said at least one receptor for tumor M2-PK pyruvate kinase isoenzyme, and   detecting any tumor M2-PK pyruvate kinase isoenzyme fragment bound to said receptor, in said stool specimen as an indication of a malignant process.