Endothelium-Derived Microparticles: Functions and Clinical Relevance

Extracellular vesicles (EVs) are receiving increased attention as circulating biomarkers of disease. Since they are produced by cells of the cardiovascular system, their contents (including lipids, proteins and microRNAs) can be measured to provide information about the relative health or dysfunction of the cardiovascular system. We recently demonstrated that healthy endothelium can package anti-inflammatory microRNAs into secreted EVs. The transfer of EV-encapsulated microRNAs can suppress monocyte activation through the targeting of genes encoding inflammatory signaling components in the recipient cell. The microRNA content of EVs therefore serve not only as a biomarker but can functionally contribute to cell-cell communication in the cardiovascular system to affect vascular health and disease. We have developed a methodology for high-throughput profiling of microRNAs in human plasma EV samples and will present data elucidating microRNA biomarkers in the setting of co-morbidities that elevate cardiovascular risk. In these settings, we are identifying predictive biomarkers of cardiovascular disease and are determining the functional importance of EVs to disease progression.