Methods for assessing atherogenesis by determining oxidized phospholipid to apolipoprotein b ratios

Abstract

The present invention relates to the analysis of oxidized phospholipids (OxPL) on apolipoprotein B-100 in patients at high risk or with documented coronary artery disease (CAD) or acute coronary syndromes (ACS) such as unstable angina and acute myocardial infarction or suspected of being at risk for ACS. Such methods are useful for diagnostic purposes and for monitoring the effects of dietary interventions or with drugs such as statins. More particularly, the present invention relates to methods for determining OxPL/apoB ratios as indices of atherosclerosis regression and plaque stability.

1 . A method for analyzing atherogenesis in a subject, the method comprising:
 a) obtaining a sample comprising plasma from a subject;   b) determining the level of oxidized phospholipid (OxPL) and the level of all detectable apoB-100 (total apoB-100) in the sample;   c) calculating an atherogenesis index (AI) for the subject comprising the ratio of the level of OxPL to the level of total apoB-100;   d) comparing the AI for the subject with AIs from subjects at high risk or with documented coronary artery disease (CAD), acute coronary syndromes (ACS), or at risk for ACS, wherein if the AI for the subject falls within the AI range from subjects at high risk or with documented CAD, ACS, or at risk for ACS, is predictive for the risk of atherogenesis in the subject.   
     
     
         2 . The method of  claim 1 , wherein the level of OxPL and the level of total apoB-100 in the sample are measured with two or more different biomolecules, wherein a first biomolecule specifically interacts with OxPL and a second biomolecule specifically interacts with apoB-100. 
     
     
         3 . The method of  claim 2 , wherein the biomolecules are antibodies. 
     
     
         4 . The method of  claim 3 , wherein the antibodies are monoclonal antibodies. 
     
     
         5 . The method of  claim 4 , wherein the antibody that interacts with OxPL is E06 or DLH3. 
     
     
         6 . The method of  claim 1 , wherein the subject is human. 
     
     
         7 . The method of  claim 1 , wherein the oxidized phospholipid is selected from the group consisting of oxidized forms of 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phos-phorylcholine (Ox-PAPC), 1-palmitoyl-2-oxovaleroyl-sn-glycero-3-phosphoryl-choline (POVPC), 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphorylcholine (PGPC), 1-palmitoyl-2-epoxyisoprostane-sn-glycero-3-phosphorylcholine (PEIPC), oxidized 1-stearoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholin-e (Ox-SAPC), 1-stearoyl-2-oxovaleroyl-sn-glycero-3-phosphorylcholine (SOVPC, 1-stearoyl-2-glutaroyl-sn-glycero-3-phosphorylcholine (SGPC), 1-stearoyl-2-epoxyisoprostane-sn-glycero-3-phosphorylcholine (SEIPC), 1-stearoyl-2-arachidonyl-sn-glycero-3-phosphorylethanolamine (Ox-SAPE), 1-stearoyl-2-oxovaleroyl-sn-glycero-3-phosphorylethanolamine (SOVPE),1-stearoyl-2-glutaroyl-sn-glycero-3-phosphorylethanolamine (SGPE), and 1-stearoyl-2-epoxyisoprostane-sn-glycero-3-phosphorylethanolamine (SEIPE). 
     
     
         8 . The method of  claim 1 , further comprising correlating the AI for the subject with:
 a) the age of the subject at the time the sample is obtained;   b) the subject's gender; and/or   c) the subject's race.   
     
     
         9 . The method of  claim 1 , further comprising correlating the AI for the subject with other atherogenesis risk factors selected from the group consisting of current smoking, hypertension, LDL cholesterol levels, and triglyceride levels. 
     
     
         10 . The method of  claim 1 , further comprising determining the level of Lp(a) liproprotein from the sample and comparing the Lp(a) liproprotein level for the subject with Lp(a) liproprotein levels from subjects at high risk or with documented CAD, ACS, or at risk for ACS, wherein if the Lp(a) liproprotein level for the subject falls within the Lp(a) liproprotein level range from subjects at high risk or with documented CAD, ACS, or at risk for ACS, is predictive for the risk of atherogenesis in the subject. 
     
     
         11 . The method of  claim 10 , further comprising correlating the Lp(a) lipoprotein levels from the subject with:
 a) the age of the subject at the time the sample is obtained;   b) the subject's gender; and/or   c) the subject's race.   
     
     
         12 . The method of  claim 10 , further comprising correlating the Lp(a) lipoprotein levels from the subject with other atherogenesis risk factors selected from the group consisting of current smoking, hypertension, LDL cholesterol levels, and triglyceride levels. 
     
     
         13 . The method of  claim 1 , wherein the CAD or ACS is unstable angina or mycocardial infarction. 
     
     
         14 . An article of manufacture comprising packaging material and, contained within the packaging material, biomolecules that preferentially interact with OxPL, apoB, and Lp(a) lipoprotein, wherein the packaging material comprises a label or package insert indicating that the biomolecules can be used for calculating an AI and for measuring Lp(a) lipoprotein levels. 
     
     
         15 . The article of  claim 14 , wherein the biomolecules are antibodies. 
     
     
         16 . The article of  claim 15 , wherein the antibodies are monoclonal antibodies. 
     
     
         17 . The article of  claim 16 , wherein the antibody that interacts with OxPL is E06 or DLH3. 
     
     
         18 . An array comprising a substrate having a plurality of addresses, each address having disposed thereon a set of one or more biomolecules, that specifically interact with OxPL, apoB, and Lp(a) lipoprotein. 
     
     
         19 . A pre-packaged diagnostic kit for analyzing a subject's risk for atherogenesis, the kit comprising an array of  claim 18 , instructions for using the array, instructions for calculating an AI by determining the ratio of the OxPL level to the apoB level, and providing information with respect to AI and Lp(a) lipoprotein levels and the risk for atherogenesis.