Circulating monocytes: Biomarkers for chronic inflammatory diseases

Abstract

Atherosclerosis is an inflammatory disease which develops very slowly and, in most cases, will not give rise to any symptoms for a very long time. Several risk factors have been found that enhance its progression like diabetes, hypertension and hypercholesterolemia, but to date, the identification of patients with unstable lesions that are at high risk of a cardiovascular event remains difficult. The use of biomarkers expressed by inflammatory cells, and especially circulating biomarkers, has gained a lot of attention because of their ability to reflect disease progression and predict the risk of a cardiovascular event. However, until now, no biomarkers, have been found that can detect high-risk patients with a good positive prognostic value. Therefore, novel sources of biomarkers are needed and one of the high-potential sources are circulating cells. Because macrophages play a crucial role in the development of atherosclerosis, a high focus has been placed on its precursor, the circulating monocyte. Recently it has become clear that the expression patterns of circulating monocytes changes in response to alterations in the diseased vessel wall, and multiple markers expressed by circulating monocytes have already been associated with disease progression like TLR, TNFα and IL-8. But more research and large trials are needed. With the circulating cell program of the CTMM project the expression of biomarkers on circulating monocytes and others cells will be investigated. Furthermore, a biosensor will be developed that is capable of measuring these biomarkers, so the development and progression of atherosclerotic disease and the identification of high-risk patients will be more accurate and easy to measure.