Microparticles are novel effectors of immunity.

Microparticles represent an intercellular communication and delivery mechanism for the efficient and effective transfer of biological information. These cargo vectors contain packages of material selectively assimilated from their parental cell, which includes bioactive lipids, integrins, cytokines, enzymes, mRNA and micro-RNA that can reprogramme recipient cells. Elevated levels of circulating microparticles are associated with a number of cardiovascular and inflammatory pathologies making them useful biomarkers for disease activity. Yet their full contribution to disease pathogenesis and its timely resolution remains to be elucidated. An emerging notion is that microparticles originating from different cell types or because of differential stimuli can exert deleterious or protective immunomodulatory actions. Herein, we discuss the bioactions of various microparticle components including genetic material, proteins and lipids and how they influence cellular behavior and ultimately host immunity.