Abstract 563: Activated Circulating Intermediate Monocytes are Associated with Subclinical Coronary Plaque in Apparently Healthy Middle-Aged Men
Background: The intermediate subset accounts for the smallest percentage of circulating monocytes yet has been associated with chronic inflammatory diseases, including CAD outcomes. It is unknown if activated intermediate monocytes (IM) are associated with coronary plaque at an earlier stage in atherosclerosis, prior to clinical manifestations.
Methods: We screened 11 healthy nondiabetic, non statin using, age-matched males for the presence and extent of coronary plaque using advanced dual-source CT angiography. Total coronary plaque (TCP) volumes (mm3) were quantified using a validated automated method and transformed to log(TCP+1). To examine monocyte subsets, whole blood was labeled to exclude non-monocytic cells. Surface CD14, CD16, TLR2, CX3CR1, and CD11b were used to confirm monocyte subsets by flow cytometry with HLA-DRhi as a marker of activation.
Results: Mean age was 54±2 (range 49 to 57); 36% were African American, 27% were smokers, and 45% had hypertension. Mean LDL-C was 121±38. The absolute number of circulating activated IM per cu mm was higher in the 6 individuals with coronary plaque compared to the 5 with no plaque (42.6±24.8 vs. 15.6±11.9, p=0.05). In bivariate analysis the number of activated IM was significantly associated with TCP (Figure, r=0.71, p=0.01). These associations were not found with classical and nonclassical monocytes.
Conclusion: In a small population of age-matched, nondiabetic apparently healthy middle-aged men not on statin therapy, the number of circulating activated IM was associated with the presence and volume of subclinical coronary plaque. Further investigation of monocyte activation prior to plaque development is ongoing.
Author Disclosures: B.G. Kral: None. L. Gama: None. D.M. Becker: None. L.R. Yanek: None. E.K. Fishman: None. D. Vaidya: None. L.C. Becker: None.
- © 2015 by American Heart Association, Inc.