MEASUREMENT OF PLASMA ANNEXIN-V BY ELISA IN THE EARLY DETECTION OF ACUTE MYOCARDIAL-INFARCTION

Annexin V is a calcium binding protein which is widely present in vari ous cells and tissues. Using annexin V which we isolated and purified from human cardiac muscle, we prepared an anti-human cardiac annexin V monoclonal antibody. Identification of annexin V was made by means of partial amino acid sequences. An enzyme-linked immunosorbent assay (E LISA) was developed using this monoclonal antibody and anti-canine car diac annexin V polyclonal antibody. With this ELISA, plasma annexin V concentration was measured in 196 normal healthy individuals, 23 acute myocardial infarction (AMI) patients who were hospitalized within 6 h after the onset of chest pain, and 130 patients with other diseases, including lung, liver and kidney disease. The plasma annexin V concent ration in normal healthy individuals was 1.7 +/- 0.6 ng/ml (mean +/- S .D.), while that in AMI patients was elevated to 13.2 +/- 6.8 ng/ml (P < 0.0001) at the time of initial blood drawing, 3.2 +/- 1.5 h after o nset of pain, and these values were higher than normal in 21 out of 23 cases (91.3%) of AMI. In all cases excepting 3, annexin V concentrati on immediately decreased after the onset of pain. The annexin V concen tration in patients with old myocardial infarction, chest pain syndrom e, valvular heart disease, lung disease and kidney disease was 1.8 +/- 0.8, 2.0 +/- 0.7, 1.7 +/- 1.1, 2.3 +/- 1.4 and 2.1 +/- 1.2 ng/ml, res pectively, being within normal limits. The values in liver disease pat ients and trauma patients were 3.7 +/- 2.7 (P < 0.05) and 3.3 +/- 2.4 (P < 0.05) ng/ml, respectively, being slightly higher than that in nor mal healthy individuals.