Isolation of Microvesicles from Plasma Samples Avoiding Lipoprotein Contamination.

Dengue is an infectious disease caused by Dengue Virus, mainly transmitted by Aedes aegypti mosquitoes. Severe dengue is a potentially fatal syndrome in consequence of overwhelmed inflammation, in which thrombocytopenia and increased vascular permeability are frequently observed. Several experimental evidences point to the participation of both microvesicles (MVs) and circulating lipoproteins in inflammatory amplification in dengue pathogenesis. On this regard, many protocols for isolating plasma MVs have shown lipoproteins as the main contaminant. This is a limitation to studies aiming at the functional characterization of MVs, since both MVs and lipoproteins can modulate inflammatory responses. Here, we describe a biphasic density-based gradient ultracentrifugation as a tool for concomitant isolation of MVs and lipoproteins without cross-contamination. Flow cytometry for MVs quantification and western blot for detection of apoB100 may be used to confirm the isolation and purity of the MVs.