Activation of Th17/Th1 and Th1, but not Th17, is associated with the acute cardiac event in patients with acute coronary syndrome.

OBJECTIVE: Th1 activation and regulatory T (Treg) cell suppression have been observed in acute coronary syndrome (ACS), including unstable angina (UA) and acute myocardial infarction (AMI). However, the role of Th17 cell or IL-17A remains controversial in ACS patients, and little is known about the role of recently discovered Th17/Th1 cells, a subset of Th17 cells, in coronary artery disease (CAD). The purpose of this study is to investigate functional changes of Th17/Th1, Th17, Th1, Th2 and Treg cells in ACS patients.

METHODS: The contents of Th17/Th1, Th17, Th1, Th2 and Treg cells, related gene expression, and plasma cytokines from CAD and control patients with normal coronary arteries (NCA) were measured by flow cytometry, real-time quantitative PCR and ELISA.

RESULTS: Th17/Th1 and Th1 cell contents and related gene expression (T-bet, IFN-γ, STAT4, RORγt, STAT3 and IL-17) were significantly increased in ACS patients, whereas plasma IFN-γ only increased in CAD patients. In contrast, Treg cell population, Foxp3 levels, and plasma TGF-β1 were decreased in ACS patients compared with stable angina (SA) and NCA patients.

CONCLUSION: The study showed activation of Th17/Th1 and Th1 cell in ACS patients, which may provide insight into the mechanisms underlying culprit plaque relevant T-cell activation in ACS patients.