Bovine Cardiac Troponin T is Not Accurately Quantified with a Common Human Clinical Immunoassay

The detection of myocardial injury in cattle caused by the ingestion of cardiotoxic compounds or cardiac diseases would be facilitated by the availability of a rapid and specific quantitative serum assay for cardiac troponins. Therefore, the accuracy of the only cardiac troponin T (cTnT) immunoassay to receive approval by the US Food and Drug Administration for the measurement of cTnT in human serum was evaluated to quantify the protein in bovine serum. Recovery experiments were performed by the addition of purified bovine cTnT to normal bovine serum. Cardiac troponin T was quantified using an immunoassay commonly used for the measurement of cTnT in human serum. The immunoassay demonstrated a well correlated (r = 0.99) and linear dose-dependent response to bovine cTnT but with poor accuracy (slope = 0.024; 95% CI = 0.018 to 0.030). The mean recovery of bovine cTnT was 2.4% across a concentration range of 10 ng/ml to 1,000 ng/ml. These studies demonstrate that a commonly used immunoassay for the measurement of cTnT in human serum demonstrates poor accuracy for the quantification of bovine cTnT.