Prostate specific antigen (PSA) -proteinase inhibitors complexes

Abstract

According to the method of the invention, immunoassays are applied to measure free PSA as well as a proteinase inhibitor complex. Free PSA and PSA complex are according to the invention measured by a non-competitive immunoassay employing at least two different monoclonal antibodies. The invention is further characterized by that the PSA proteinase inhibitor complex of interest is formed either with α 1 -antichymotrypsin, α 1 -protease inhibitor (API) or α 2 -macroglobulin. Moreover, the invention is characterized by that free PSA, the PSA-proteinase inhibitor complex and their ratio are applied in the diagnosis of patients with prostate cancer.

1 . An immunoassay of prostate-specific antigen (PSA) characterized by that in the immunoassay of prostate-specific antigen (PSA) 
 an amount of prostate-specific antigen complexed with a proteinase inhibitor and/or    an amount of free non-complexed prostate-specific antigen and/or    an amount of the total prostate-specific antigen are measured:    
     
     
         2 . An immunoassay according to  claim 1  characterized by that 
 the PSA-proteinase inhibitor complex (complexed PSA) and/or  
 the free non-complexed prostate-specific antigen (free PSA) and/or  
 the total prostate-specific antigen (total PSA) are measured by a non-competitive immunoassay.  
 
     
     
         3 . An immunoassay according to  claim 2  characterized by that 
 the PSA-proteinase inhibitor complex (complexed PSA) and/or  
 the free non-complexed prostate-specific antigen (free PSA) and/or  
 the total prostate-specific antigen (total PSA) are measured by a non-competitive immunoassay employing at least two different monoclonal antibodies.  
 
     
     
         4 . An immunoassay according to  claim 3  characterized by that the monoclonal antibodies used for the recognition of the PSA-proteinase inhibitor complex (complexed PSA) bind either to 
 prostate-specific antigen (PSA), or to  
 the PSA-proteinase inhibitor complex (complexed PSA) or to  
 the proteinase inhibitor.  
 
     
     
         5 . An immunoassay according to  claim 4  characterised by that the proteinase inhibitor is a,-antichymotrypsin.  
     
     
         6 . An immunoassay according to  claim 4  characterized by that the proteinase inhibitor is o-proteinase inhibitor.  
     
     
         7 . An immunoassay according to  claim 4  characterized by that the proteinase inhibitor is macroglobulin.  
     
     
         8 . An immunoassay according to  claim 2  characterized by that the ratio between the free non-complexed prostate-specific antigen (free PSA) and the PSA-proteinase inhibitor complex (complexed PSA) is determined.  
     
     
         9 . An immunoassay according to  claim 2  characterized by that the ratio between the free non-complexed prostate-specific antigen (free PSA) and the total prostate-specific antigen (total PSA) is determined.  
     
     
         10 . An immunoassay according to  claim 2  characterized by that the ratio between the PSA-proteinase inhibitor complex (complexed PSA) and the total prostate-specific antigen (total PSA) is determined.