Acid-labile subunit (ALS) of insulin-like growth factor binding protein complex

Abstract

The acid-labile sub-unit (ALS) of insulin like growth factor binding protein complex in biologically pure form is described. ALS has a molecular weight between 80-115 kd as determined by SDS polyacrylamide gel electrophoresis, run under reducing conditions; and a partial N-terminal amino acid sequence as follows: Gly(Ala)AspProGlyThrProGlyGluAlaGlu (SEQ ID NO:1) GlyProAlaCysProAlaAlaCys wherein the first amino acid may be Gly or Ala. Also described are methods of producing ALS, compositions containing the in-vivo IGF protein complex, methods of detecting ALS in body fluids, recombinant nucleic acid sequences encoding ALS, and expression vectors and host cells containing such nucleic acid sequences.

1 - 38 . (canceled)  
     
     
         39 . An antibody reagent that binds to acid labile subunit (ALS).  
     
     
         40 . The antibody of  claim 39 , wherein said antibody is a monoclonal antibody.  
     
     
         41 . The antibody of  claim 39 , wherein said antibody is labeled.  
     
     
         42 . The antibody of  claim 41 , wherein said label is a fluorescent group.  
     
     
         43 . The antibody of  claim 39 , wherein said ALS comprises one or more carbohydrate chains.  
     
     
         44 . The antibody of  claim 39 , wherein said ALS comprises the amino acid sequence (Gly/Ala)-Asp-Pro-Gly-Thr-Pro-Gly-Glu-Ala-Glu-Gly-Pro-Ala-Cys-Pro-Ala-Ala-Cys-Ala.  
     
     
         45 . The antibody of  claim 39 , wherein said ALS has an approximate molecular weight of between 80 kDa and 115 kDa as determined by sodium docecyl sulfate-polyacrylamide gel electrophoresis.  
     
     
         46 . The antibody of  claim 39 , wherein said ALS is present in a complex with acid-stable insulin-like growth factor (IGF) binding protein BP-53 and IGF.  
     
     
         47 . The antibody of  claim 39 , wherein said ALS is recombinant ALS.