Antibodies to modified human igf-1/e peptides

Abstract

High-specificity antibodies can distinguish between modified (e.g, hIGF-1/Ea 3mut) and endogenous wild-type human IGF-1 proteins. These antibodies have little or no cross-reactivity with hIGF-1 or hIGF-2. They also have little or no cross-reactivity with rodent IGF-1 or IGF-2. The antibodies can be used in pharmacokinetic (PK)/pharamcodynamic (PD) assessments of IGF-1/E peptides that have been administered to humans or animals. A sandwich ELISA assay, using the antibody of the invention as a capture antibody, can quantify the mutant IGF-1/E proteins in samples.

1 . An antibody that binds immunospecifically to peptide GPTLCGAELV (SEQ ID NO: 1) but does not bind immunospecifically to peptide GPETLCGAELV (SEQ ID NO: 2). 
     
     
         2 . An antibody according to  claim 1 , wherein the peptide GPTLCGAELV (SEQ ID NO: 1) and/or the peptide GPETLCGAELV (SEQ ID NO: 2) form parts of larger peptides. 
     
     
         3 . An antibody that binds immunospecifically to peptide PAKSAVRAQR (SEQ ID NO: 6) but does not bind immunospecifically to peptide PTKAARSIRAQR (SEQ ID NO: 7). 
     
     
         4 . An antibody according to  claim 3 , wherein the peptide PAKSAVRAQR (SEQ ID NO: 6) and/or the peptide PTKAARSIRAQR (SEQ ID NO: 7) form parts of larger peptides. 
     
     
         5 . An antibody selected from the group consisting of QQ2, QQ5 and QQ6. 
     
     
         6 . A hybridoma expressing an antibody of  claim 5 . 
     
     
         7 . An isolated polypeptide comprising the sequence GPTLCGAELV (SEQ ID NO: 1), CPAKSAVRAQR (SEQ ID NO: 5) or PAKSAVRAQR (SEQ ID NO: 6). 
     
     
         8 . A nucleic acid encoding an antibody according to  claim 5 . 
     
     
         9 . A vector comprising a nucleic acid according to  claim 8 . 
     
     
         10 . A host cell comprising a vector according to  claim 9 . 
     
     
         11 . An Enzyme-Linked ImmunoSorbent Assay (ELISA) method for the detection of a modified insulin-like growth factor 1/E (IGF-1), comprising the step of:
 (i) detecting a modified insulin-like growth factor 1/E (IGF-1) using an antibody according to  claim 1  as a capture antibody.   
     
     
         12 . An affinity chromatographic method for the purification of a modified insulin-like growth factor 1/E (IGF-1) from a solution, wherein the affinity chromatographic method comprises the step of:
 (i) purifying a modified insulin-like growth factor 1/E (IGF-1) from a solution using an antibody according to  claim 1 .   
     
     
         13 . A method of determining the level of a modified IGF-1/E protein in a patient, comprising the step of:
 (i) detecting the modified IGF-1/E in a blood sample obtained from a patient using an antibody according to  claim 1 .   
     
     
         14 . A method of maintaining an optimal dose of a modified IGF-1/E in a patient in need thereof, comprising the step of:
 (i) detecting the modified IGF-1/E in a blood sample from a patient who has been administered a modified IGF-1/E, using an antibody according to  claim 1 ,   where the level of modified IGF-1/E in the patient blood sample is below a pre-determined optimum level, administering a further dose of said modified IGF-1/E to said patient.   
     
     
         15 . A method of treating a patient who is suffering from a muscle disorder comprising the steps of:
 (i) determining the serum concentration of a modified IGF-1/E in a blood sample obtained from a patient who has previously been administered the modified IGF-1/E, using an antibody according to  claim 1 , wherein the antibody binds immunospecifically to the modified IGF-1/E, and   (ii) administering additional modified IGF-1/E to the patient if the serum concentration of hIGF-1/Ea 3mut is below a pre-determined optimum level.   
     
     
         16 . An Enzyme-Linked ImmunoSorbent Assay (ELISA) method for the detection of a modified insulin-like growth factor 1/E (IGF-1), comprising the step of:
 (i) detecting a modified insulin-like growth factor 1/E (IGF-1) using an antibody according to  claim 3  as a capture antibody.   
     
     
         17 . An affinity chromatographic method for the purification of a modified insulin-like growth factor 1/E (IGF-1) from a solution, wherein the affinity chromatographic method comprises the step of:
 (i) purifying a modified insulin-like growth factor 1/E (IGF-1) from a solution using an antibody according to  claim 3 .   
     
     
         18 . A method of determining the level of a modified IGF-1/E protein in a patient, comprising the step of:
 (i) detecting the modified IGF-1/E in a blood sample obtained from a patient using an antibody according to  claim 3 .   
     
     
         19 . A method of maintaining an optimal dose of a modified IGF-1/E hIGF-1/Ea 3mut in a patient in need thereof, comprising the step of:
 (i) detecting the modified IGF-1/E hIGF-1/Ea 3mut in a blood sample from a patient who has been administered a modified IGF-1/E, using an antibody according to  claim 3 ,   where the level of modified IGF-1/E hIGF-1/Ea 3mut in the patient blood sample is below a pre-determined optimum level, administering a further dose of said modified IGF-1/E hIGF-1/Ea 3mut to said patient.   
     
     
         20 . A method of treating a patient who is suffering from a muscle disorder comprising the steps of:
 (i) determining the serum concentration of a modified IGF-1/E in a blood sample obtained from a patient who has previously been administered the modified IGF-1/E, using an antibody according to  claim 3 , wherein the antibody binds immunospecifically to the modified IGF-1/E, and   (ii) administering addition modified IGF-1/E to the patient if the serum concentration of modified IGF-1/E is below a pre-determined optimum level.