Circulating Mononuclear Cell Transcriptomes in Patients with Atherosclerotic Coronary Artery Disease

Monocytes and T-cells play an important role in the development of atherosclerotic coronary artery disease (CAD). Differences in transcriptional activity of these cells might reflect the individual's atherosclerotic burden. Transcriptome analysis of circulating mononuclear cells from carefully matched atherosclerotic and control patients will potentially provide insights into the pathophysiology of atherosclerosis and supply biomarkers for diagnostic purposes. From patients undergoing coronary angiography because of anginal symptoms, we carefully matched 18 patients with severe triple-vessel CAD to 13 control patients without signs of CAD on angiography. All patients were on statin and aspirin treatment. RNA from circulating CD4+ T-cells, CD14+ monocytes, lipopolysaccharide-stimulated monocytes, macrophages and CD34+ progenitor cells was subjected to genome-wide expression analysis. Only CD14+ monocytes demonstrated that a small number of genes involved in activation was overexpressed in control patients, which was verified by real-time polymerase-chain reaction. In this pilot study, cautious matching of patients with severe atherosclerotic CAD with control patients without angiographic signs of coronary atherosclerosis did not reveal differences in transcriptional activity in four out of five different mononuclear cell types. In resting monocytes from patients without overt CAD some inflammatory genes were overexpressed as compared to patients with severe CAD. Large inter-individual variability prevented the use of single differentially expressed genes as biomarkers.

keywords: disease-state analysis macrophages expression profiling by array