Inflammation and activation of immune cells play important roles in the pathogenesis of atherosclerosis. We investigated the activation status of plasma inflammatory markers and immune cells in angina patients.

We analyzed the plasma level of C-reactive protein (CRP) as a marker of inflammation in 24 patients with angina pectoris (12 unstable angina, 12 stable angina), and 12 normal subjects. The degree of activation of peripheral blood monocytes was assessed by Northern analysis of pro-atherogenic cytokines and the activation status of T-lymphocytes was measured by flow-cytometric analysis of HLA-DR expression on T-cells.

Plasma level of CRP was highest in unstable angina patients (1.63±0.70 mg/l) and lowest in the control subjects (0.22±0.08 mg/l)(p=0.03). We also observed a high correlation between CRP level and the occurrence of minor and major coronary events during 6 months of follow-up. The percentage of HLA-DR positive T-lymphocyte was significantly increased in the unstable angina patients (26.8±1.4%) compared with that in the control (14.7±1.2%)(p=0.0053). When baseline levels of cytokine mRNA were measured in monocytes, the percentages of the patients expressing higher than normal levels of IL-8, IL-1b, MCP-1, and TF mRNAs was 37.5, 29.2, 33.3, and 37.5%, respectively (p=0.0143, 0.0371, 0.0233, and 0.0143, respectively). Basal mRNA levels of interleukin (IL)-8, tissue factor (TF), IL-1b and monocyte chemoattractant protein-1 (MCP-1) showed a strong correlation with each other (p<0.01 in all combination) but not with tumor necrosis factor (TNF)-alpha or transforming growth factor (TGF)-beta1.

We observed increase in plasma CRP levels and activation of T-lymphocytes in angina patients. These results may help further classification of angina patients according to the activation of inflammatory markers and understanding the prognosis of the disease.