Background: Coronary atherosclerosis includes an activation of circulating T lymphocytes. Statins exert anti-inflammatory effects beyond lipid lowering. Whether these properties influence systemic T lymphocytes is unclear.
Methods: To investigate the effect of atorvastatin on circulating T-lymphocyte subsets producing proinflammatory and anti-inflammatory cytokines (interferon gamma [IFN-gamma(+)], interleukin 2 [IL-2(+)], IL-4(+), and IL-10(+)) and on the T-cell-activating soluble CD40 ligand (sCD40L), 30 hypercholesterolemic patients with angiographically documented stable coronary artery disease (CAD) were randomized to placebo or atorvastatin (20 mg/d) for 3 months. Eight healthy volunteers served as controls. Levels of peripheral cytokine-producing CD4+ and CD8+ T cells and their CD28- subsets were determined by FACS. Serum soluble CD40L was measured with ELISA.
Results: IL-2(+) T lymphocytes and sCD40L levels were higher in patients with CAD compared with controls, whereas IFN-gamma(+) and anti-inflammatory IL-4(+) and IL-10(+) T lymphocytes were similar. Levels of IL-2(+), IFN-gamma(+), IL-4(+), and IL-10(+) T-cell subsets as well as CD28- T lymphocytes were neither changed by atorvastatin nor by placebo, whereas sCD40L was lowered only in atorvastatin-treated patients (P < .01).
Conclusion: Circulating IL-2(+) T lymphocytes are increased in patients with stable CAD reflecting an activation of the global immune system, but are not influenced by atorvastatin therapy. The elevated levels of platelet-derived T-lymphocyte-stimulating sCD40L are decreased by atorvastatin probably reflecting an atheroprotective effect. Hence, sCD40L may be an additional biomarker to be considered when evaluating the treatment effects of statins in patients with stable CAD.