Ious EV preparations. Methods: EV samples had been prepared from platelet free of charge plasma (PFP EVs) and from red blood cell concentrate (REVs), and had been thoroughly characterized by flow MMP-1 Proteins Molecular Weight cytometry, TEM, DLS and infrared spectroscopy. Wheat germ agglutinin (WGA), Alexa Fluor 647 Conjugate, was applied as a basic glycoprotein/membrane label, and FITC conjugated antihuman CD235A was utilized for labeling REVs. HPLC-SEC measurements had been performed making use of a 200 mm x five mm glass column filled with Sepharose CL-2B cross linked agarose gel and with a JASCO PU-2089 pump supplemented with an FP-4020 fluorescence detector. Benefits: Sepharose CL-2B gel is capable of separating EVs from soluble proteins and lipoprotein particles, that is also demonstrated in our HPLC-SEC measurements on PFP EVs and REVs. On account of these characteristics, removing the unbound WGA and anti-CD235a markers prior to the HPLC-SEC measurement was not important. With other words, the fluorescence chromatograms straight give the labeling efficiency from the utilized markers. This enabled the quantification of EV bound markers by taking into account the initial concentration from the labels.Thursday, 03 MayEV concentrations corresponding to as low as 1 ng of WGA and 10 ng of CD235a were measured by the proposed strategy. Summary/Conclusion: This study provides the proof-of-concept of utilizing on the web fluorescence detection in HPLC-SEC, which serves as a fast, sensitive and specific method for the characterization of EV preparations. The use of WGA as a general membrane marker provides a sensitive way for the detection of EVs, whereas certain fluorescent antibody conjugates – such as CD235a in our case – is often utilised for phenotyping of EVs from various origin. Funding: This work was supported by the National Study, Development and Innovation Office (Hungary) below grant numbers [PD 121326 and NVKP_16-1-2016-0007]. ZV was supported by the Janos Bolyai ADAMTS16 Proteins site Analysis Fellowship.LBT01.Phenotyping of EVs by multiwavelength fluorescence nanoparticle tracking Analysis Clemens Helmbrecht Particle Metrix GmbH, Inning, GermanyMethods: We labeled THP-1 human monocytic leukemia cells with the lipophilic dyes PKH67 and DiI. After labeling, small (d 200 nm) and medium sized (d: 20000 nm) EVs had been isolated by differential centrifugation and gravity-driven filtration in the supernatant. To exclude the probable effect of bovine lipoproteins, we made use of a 24 h serum free of charge incubation for EV production. Sulfate-aldehyde latex beads have been coated with native, oxidized and acetylated LDLs also as with purified native apolipoproteins (apoA1, apoB, apoC2 and apoE). Right after blocking with BSA and glycin, fluorescently labeled EVs were incubated with the beads. Fluorescence of the beads resulting from that in the attached EVs, was analysed by flow cytometry. EV adhesion to distinct coatings was compared each towards the bare and for the blockedonly beads. Benefits: Each compact and medium sized EVs showed substantial adhesion to apoB (p 0.05). There was no difference amongst the signals of smaller and medium EVs. We also observed adhesion to native, oxidized and acetylated LDLs, apoA1 and apoC2. Having said that, within the case of apoE, no binding was detected. Summary/Conclusion: The interaction between LDL and EVs may possibly be mediated by the apolipoprotein B element of LDL. Funding: This perform was supported by: National Analysis, Development and Innovation Office NKFIH, Hungary [OTKA11958, OTKA120237, NVKP_16-1-2016-0017], Ministry for National Ec.