AUTOANTIBODY TITERS TO OXIDIZED LOW-DENSITY-LIPOPROTEIN IN PATIENTS WITH CORONARY ATHEROSCLEROSIS

Oxidation of low-density lipoprotein (LDL) is considered to be the ini tial step in the atherosclerotic process. Autoantibodies to oxidized L DL (ox-LDL) have been detected in human serum. We used an enzyme-linke d immunosorbent assay technique to measure autoantibody titers in 63 n ormal subjects and patients with coronary artery disease. Thirty-five patients underwent coronary angiography for suspected coronary artery disease. Patients were divided into the following categories: group 1, 20 healthy young volunteers; group 2, 8 patients age-matched to the c atheterization patients; group 3, 10 patients with normal coronary ang iograms; and group 4, 25 patients with angiographic coronary artery di sease. Autoantibody titers to ox-LDL were group 1, 0.142 +/- 0.023; gr oup 2, 0.197 +/- 0.039; group 3, 0.183 +/- 0.038; and group 4, 0.340 /- 0.026. There was no statistical difference among groups 1, 2, and 3 , but the difference between these groups and group 4 was highly signi ficant (p < 0.05). This study demonstrates that (1) autoantibodies to ox-LDL can be detected in normal subjects and in patients with abnorma l coronary angiograms and (2) significantly higher titers of autoantib odies to ox-LDL were seen in patients with angiographic evidence of co ronary artery disease.