CD14+CD16+ monocytes in coronary artery disease and their relationship to serum TNF-α levels
Axel Schlitt(1*), Gunnar H. Heine(2*), Stefan Blankenberg(1), Christine Espinola-Klein(1), Joern F. Dopheide(1), Christoph Bickel(1), Karl J. Lackner(1), Mete Iz(1), Juergen Meyer(1), Harald Darius(1), Hans J. Rupprecht(1)
(1)Department of Medicine II and Institute of Clinical Chemistry and Laboratory Medicine, Johannes Gutenberg University, Mainz,Germany (2)Department of Medicine IV, University of the Saarland, Homburg/Saar, Germany
Summary Monocytes play a central role in the inflammatory diseaseatherosclerosis. CD14+CD16+ monocytes are consideredproinflammatory monocytes, as they have an increased capacityto produce proinflammatory cytokines, such as TNF-α, andare elevated in various inflammatory diseases.We hypothesizedthat patients with coronary artery disease (CAD) haveincreased levels of CD14+CD16+ monocytes, and thatCD14+CD16+ monocytes are associated with inflammationmarkers. We investigated CD14+CD16+ monocytes in 247patients with CAD and 61 control subjects using flow cytometry.In addition serum concentrations of TNF-α, IL-6, andHs-CRP were assessed. Patients with CAD had higher levels ofCD14+CD16+ monocytes than controls (13.6% versus 11.4%;p<0.001). Logistic regression analysis including quartiles of CD14+CD16+ monocytes showed that CD14+CD16+ monocyteswere associated with prevalence of CAD (OR 4.9, 95% CI2.5–19.1, for subjects in the fourth quartile in comparison tosubjects in the first quartile). The association betweenCD14+CD16+ monocytes and CAD remained independentlysignificant after adjustment for most potential confounders(OR 5.0, 95% CI 1.2-20.0). Serum concentrations of TNF-αwere elevated in subjects within the highest quartiles ofCD14+CD16+ monocytes (p=0.018). Our study showed thatincreased numbers of CD14+CD16+ monocytes are associatedwith coronary atherosclerosis and TNF-α. In accordance,recent animal studies suggest a possibly important role of thesemonocytes in the development of atherosclerosis.