The Th17/Treg imbalance in patients with acute coronary syndrome

Atherosclerosis is a chronic inflammatory disease regulated by T lymphocyte subsets. Recently, CD4+CD25+Foxp3+ regulatory T (Treg) cells and Th17 cells have been described as two distinct subsets from Th1 and Th2 cells and have the opposite effects on autoimmunity. Th17/Treg balance controls inflammation and may be important in the pathogenesis of plaque destabilization and the onset of acute coronary syndrome [ACS, including unstable angina (UA) and acute myocardial infarction (AMI)]. To assess whether this balance was broken in patients with coronary heart disease, we detected Th17/Treg functions on different levels including cell frequencies, related cytokine secretion and key transcription factors in patients with AMI, UA, stable angina (SA) and controls. The results demonstrated that patients with ACS revealed significant increase in peripheral Th17 number, Th17 related cytokines (IL-17, IL-6 and IL-23) and transcription factor (RORγt) levels and obvious decrease in Treg number, Treg related cytokines (IL-10 and TGF-β1) and transcription factor (Foxp3) levels as compared with patients with SA and controls. Results indicate that Th17/Treg functional imbalance exists in patients with ACS, suggesting a potential role for Th17/Treg imbalance in plaque destabilization and the onset of ACS.