UNLABELLEDTo investigate the effect of immune response mediated by the T cells stimulated with the specific antigen (oxidized low-density lipoprotein, oxLDL) on plaque stability in coronary heart disease.

METHODSThis study involved 20 patients with acute myocardial infarction (AMI), 34 with unstable angina pectoris (UAP), 27 with stable angina pectoris (SAP) and 22 healthy control subjects. With MTS/PMS colorimetric assay, the T cells from all the subjects were tested for proliferative response to stimulation by 5 microg/ml oxLDL and 5 microg/ml low-density lipoprotein (LDL). Interferon-gamma (IFN-gamma) concentration in the proliferative response of the T cells was measured with enzyme-linked immunosorbent assay (ELISA).

RESULTSThe proliferative response of the T cells elicited by 5 microg/ml oxLDL stimulation was significantly higher in the AMI and UAP groups than in the SAP and control groups (P<0.05). Similarly, IFN-gamma concentration in the proliferative response of the T cells to 5 microg/ml oxLDL stimulation was significantly higher in the former two groups (P<0.05). In the AMI and UAP groups, 5 microg

CONCLUSIONThe immune response mediated by the T cells to specific antigen stimulation, especially the immune response mediated by T helper type 1 (Th1) cells secreting IFN-gamma, may play an important role in the plaque instability and the occurrence of acute coronary syndrome.