Relationship between toll-like receptor 4 levels in aorta and severity of atherosclerosis.

Objective: To investigate the relationship between levels of toll-like receptor 4 (TLR4) protein in aortic tissue and the severity of atherosclerosis in patients undergoing coronary artery bypass graft (CABG) surgery. Methods: Samples of ascending aorta and renal artery were collected from patients undergoing CABG surgery or kidney donation, respectively. TLR4 levels were determined by immunohistochemistry. Coronary angiography was performed to determine atherosclerosis severity via Gensini score. Results: TLR4 was present at high levels in aortic tissues from patients (n = 46), and was absent from renal artery tissue (controls; n=11). There was a significant positive correlation between Gensini score and TLR4 level in the patient group. Conclusions: TLR4 may play an important role in atherosclerosis and could be a potential therapeutic target for treatment of coronary artery disease. Discarded aortic tissue obtained during CABG surgery provides a new approach to the study of the pathogenesis of atherosclerosis.