Methods for Detecting Asymmetric Dimethylarginine in a Biological Sample

Abstract

The present invention provides methods of detecting asymmetric dimethylarginine (ADMA) in a sample, particularly a sample that may contain symmetrical dimethylarginine (SDMA) and/or arginine. The methods generally involve modifying any SDMA and arginine in the sample such that SDMA and arginine are readily distinguishable from ADMA; and detecting ADMA. The invention further provides antibodies specific for ADMA; antibodies specific for modified SDMA; and antibodies specific for modified arginine. The invention further provides kits for practicing the subject methods.

1 .- 9 . (canceled) 
   
   
       10 . An antibody that binds specifically to asymmetric dimethylarginine. 
   
   
       11 . The antibody of  claim 10 , wherein said antibody is detectably labeled. 
   
   
       12 . An antibody that binds specifically to modified symmetric dimethylarginine (SDMA), wherein the guanidino nitrogens of the SDMA are modified by reaction with an α-dicarbonyl compound. 
   
   
       13 . A kit for detecting asymmetric dimethylarginine (ADMA) in a sample, the kit comprising:
 an α-dicarbonyl agent that modifies the guanidino nitrogens of SDMA and the guanidino nitrogens of arginine; and   an antibody that binds to ADMA.   
   
   
       14 . The kit of  claim 13 , further comprising an antibody that binds α-dicarbonyl-modified SDMA, and an antibody that binds α-dicarbonyl-modified L-arginine. 
   
   
       15 . The antibody of  claim 10 , wherein the antibody is isolated or artificial. 
   
   
       16 . The antibody of  claim 10 , wherein the antibody is a polyclonal antibody. 
   
   
       17 . The antibody of  claim 10 , wherein the antibody is a monoclonal antibody. 
   
   
       18 . The antibody of  claim 10 , wherein the antibody is coupled to an insoluble support. 
   
   
       19 . The antibody of  claim 18 , wherein the insoluble support is a plastic surface, a membrane, a bead, a colloidal particle, an affinity column matrix, or a test strip. 
   
   
       20 . The antibody of  claim 10 , wherein the antibody comprises a radioisotope, an enzyme, a fluorescent label, or a fluorescent protein. 
   
   
       21 . The antibody of  claim 12 , wherein the antibody is detectably labeled. 
   
   
       22 . The antibody of  claim 12 , wherein the antibody is isolated or artificial. 
   
   
       23 . The antibody of  claim 12 , wherein the antibody is a polyclonal antibody. 
   
   
       24 . The antibody of  claim 12 , wherein the antibody is a monoclonal antibody. 
   
   
       25 . The antibody of  claim 12 , wherein the antibody is coupled to an insoluble support. 
   
   
       26 . The antibody of  claim 25 , wherein the insoluble support is a plastic surface, a membrane, a bead, a colloidal particle, an affinity column matrix, or a test strip. 
   
   
       27 . The antibody of  claim 12 , wherein the antibody comprises a radioisotope, an enzyme, a fluorescent label, or a fluorescent protein. 
   
   
       28 . The kit of  claim 13 , wherein the α-dicarbonyl compound is selected from biacetyl, pyruvic acid, glyoxal, methyglyoxal, deoxyosones, 3-deoxyosones, malondialdehyde, 2-oxopropanal, phenylglyoxal, 2,3-butanedione, and 1,2-cyclohexanedione. 
   
   
       29 . The kit of  claim 14 , wherein the antibody is detectably labeled. 
   
   
       30 . The kit of  claim 14 , wherein the antibody is coupled to an insoluble support. 
   
   
       31 . The kit of  claim 30 , wherein the insoluble support is a plastic surface, a membrane, a bead, or a test strip.