Real-Time Polymerase Chain Reaction Coupled Detection of Cardiac Troponin I with the Bio-Bar Code AssayPublic Deposited
Every year millions of Americans go to the emergency room with symptoms of a heart attack. More than half a million Americans die each year of myocardial infarctions (MI) caused by coronary heart disease (CHD). CHD detection is currently limited to EKG analyses of electrical signals generated by the heart or to protein immunoprecipitation assays of proteins released from cardiac cell death. Neither method has a sensitivity low enough to detect minor damage to the heart or to definitively diagnose acute myocardial infarctions (AMI). False positive admissions to the emergency room for AMI waste billions of dollars annually. Unambiguous diagnosis of AMI could save millions of dollars as well as shorten the crucial time before drugs are administered to mitigate the effects of a recent heart attack. Increasing the sensitivity of protein detection specific to AMI might improve diagnosis. Using the bio-bar code assay developed in the Mirkin lab, ultrasensitive detection of proteins can be achieved. In particular, with a real-time PCR coupled bio-bar code assay, sensitivity of cardiac troponin, a protein highly specific to cardiac cell death, can be extended to 500 fM. This is 100 times more sensitive than traditional protein immunoprecipitation assays and might play a key role both in the unambiguous diagnosis of acute MI and in monitoring the progression from minor MI to acute MI.