N on the measured concentrations by 20 compared to the existing regular. We will present preliminary data from the study. Summary/conclusion: This approach will allow a closer approximation of the size of vesicles and strengthen the reproducibility of concentration measurements with diverse flow cytometers. There may be a distinction involving assumed and true refractive index, which would lead to a difference involving the preferred and actual vesicle size range. However, this refractive index difference is compact in comparison to the error made by assuming the refractive index of polystyrene to become equal to vesicles and will not have an effect on the concentration reproducibility.cytometers (FCMs) with and devoid of imaging. Approaches: Liposomes have been ready by a modification from the Szoka/Papahadjopoulos filtration approach. Avanti Polar lipids had been dissolved with cholesterol and lipophilic dye (Dil and DiO) in chloroform. Sizing of liposomes was performed by the repeated filtration by way of different sizes of polycarbonate filter. Distinctive sizes of liposomes (0.200 mm labelled with Dil; 0.2, 0.four and 0.6 mm labelled with DiO) had been confirmed by dynamic light scattering (DLS) and detected by imaging flow cytometry (Imagestream MKII, ISX) and traditional FCM. Geometric suggests (GM) on the fluorescence intensity from the 02699931.2015.1049516 DiO had been calculated for the 3 distinct sizes of liposomes in diluted and undiluted samples (1:1, 1:100, 1:1000). Results: ISX can clearly resolve all liposomes above background (buffer only), whereas only a small portion is detected by FCM. In comparison to polystyrene beads, liposomes have significantly decrease side scatter intensity. Calculation of the fluorescence geometric suggests of 3 distinct sizes of liposomes (approx. 0.2 mm, 0.4 mm and 0.six mm) showed a linear increase in fluorescence suggests. Hence, a calibration curve for sizing of MP might be established utilizing the fluorescence intensity. Dilution of liposomes demonstrated swarm detection by FCM as indicated by a lower in fluorescence GM with FCM but not with ISX. Summary/ conclusion: Lipid-based vesicles like fluorescently labelled liposomes may be clearly detected and visualized by imaging flow cytometry, whereas FCM was only in a position to detect swarms of liposomes. As their scatter profile is close to MPs they provide a much more correct method to define the decrease degree of detection sensitivity of your instruments. The usage of several sizes of fluorescently labelled liposomes provides a possible method for the sizing of MPs.O8B-Separation of dendritic cell-derived extracellular vesicles by means of density gradients Joanna Kowal1, Marina Colombo1, Guillaume Arras2, Florent Dingli2, Damarys Loew2, Mercedes Tkach1 and Clotilde Thery1 INSERM U932, Paris, France; 2Laboratory of Proteomic Mass Spectrometry, Institut Curie, Centre de Recherche, Paris, FranceO8B-Fluorescently labelled liposomes for defining instrument detection sensitivity for measuring microparticles by flow cytometry with and devoid of imaging Uta Erdbruegger1, Christine Rudy1, Alexander Klibanov2 and Joanne Lannigan1 Medicine/Nephrology, University of Virginia Health Method, Charlottesville, VA, USA; 2Medicine/Biomedical Engineering, University of Virginia Well being Program, Charlottesville, VA, USA; 3Department of MicroFruquintinib Biology, Immunology and Cancer Biology, University of dar.12324 Virginia Wellness System, Charlottesville, VA, USAIntroduction: Study groups propose use of polystyrene beads (PSB) to standardize flow cytometers for microparticle (MP) det.