On the other hand, further analysis (Fig. 3) revealed that MerTK expression in M2 macrophages were only significantly higher than M1 macrophages in no apparent CAD patients [12.58 ± 4.40 versus 6.58 ± 1.37, p = 0.040] but not in non-obstructive CAD as well as obstructive CAD patients. Here, MERTK is linked to coronary artery disorder.