Association between the level of CD4(+) T lymphocyte microRNA-155 and coronary artery disease in patients with unstable angina pectoris

OBJECTIVE: To study the association between the expression of microRNA-155 (miRNA-155) in peripheral blood CD4(+) T lymphocytes and the level of serum interferon-γ (IFN-γ) concentration and the severity of coronary artery disease (CAD). METHODS: After coronary angiography, 252 patients with suspected unstable angina pectoris (UAP) were divided into the UAP group (128 patients with CAD confirmed by angiography) and the control group (124 patients without CAD confirmed by angiography). Fresh peripheral blood was extracted 16–24 h before coronary angiography, CD4(+) T lymphocytes was tested using immunomagnetic beads, the expression of miRNA-155 was tested using quantitative PCR and the expression of IFN-γ was tested using enzyme-linked immunosorbent assay (ELISA). According to the results of angiography, Gensini score of coronary artery lesions was analyzed. Furthermore, we also analysis the association between the level of miRNA-155 in peripheral blood CD4(+) T lymphocytes, the level of serum IFN-γ and Gensini score of coronary lesion. RESULTS: The levels of miRNA-155 (0.49 ± 0.08 vs. 0.23 ± 0.09) and IFN-γ (227.58 ± 26.01 vs. 141.23 ± 17.89) in the UAP group were significantly higher than that of the control group, the difference was statistically significant. The level of miRNA-155 and IFN-γ were positively correlated with Gensini score of CAD (r = 0.534, r = 0.713, respectively, all P < 0.05). The level of miRNA-155 was positively correlated with the level of IFN-γ (r = 0.686, P < 0.05). CONCLUSIONS: The level of miRNA-155 in peripheral blood CD4(+) T lymphocytes and the level of IFN-γ are closely correlated with the severity of CAD.