Is usually transferred amongst neighbouring cells in mammalian tissue to handle the expression of genes in each donor and recipient cells. How the extracellular vesicle (EV)-derived miRNAs are finding internalized and develop into functional in target cells is an unresolved question. Techniques: We used mammalian cells in culture to study the EV-mediated miRNA delivery to target cells. Making use of miR-122 adverse HeLa cells as recipient cells and miR122 containing exososmes isolated from miR-122 optimistic cells, we’ve delineated the mechanistic detail of your import process. Outcomes: We’ve got identified that, through a distinctive mechanism, the EV-associated miRNAs which can be mostly single stranded can get RelB list loaded with the Ago proteins present inside the target cells to develop into functional there. The loading of EV-derived miRNAs to host cells Ago proteins isn’t dependent around the Dicer1 that otherwise essential for the loading of the Ago proteins with double stranded miRNAs ahead of one strand get cleaved and dislodged from Ago2. The EV-derived miRNA loading of Ago2 takes place around the endosomal membrane where the pH dependent fusion of your internalized EV membrane with endosomal membrane releases the miRNAs thatJOURNAL OF EXTRACELLULAR VESICLESget loaded with unloaded Ago2 present on the endosomal membrane. This process is depenent on memebrane dynamics and restriction of memebrane dynamics either as a result of mitochondrial depolarization or other methods impacts the loading of EV-derived miRNAs with Ago2. Leishmania donovani, a protozoan parasite affect membrane dynamics in infected macrophage cells and hence it restrict the internalization of miR-122 containing EVs that otherwise result in an inflammatory response in mammalian macrophage-a method detrimental for the pathogen. Summary/Conclusion: thus we conclude that Leishmania donovani Restricts Retrograde DicerIndependent Loading of Extracellular Single Stranded miR-122 in Host Cell Agos to stop Inflammatory Response. Funding: SERB, Dept of Science and Technology, Govt. of India and Swarnajayanti Fellowship Fund, Dept of Science and Technologies, Govt. of India.OS23.Engineering of extracellular vesicles for surface display of targeting ligands Elisa L aro-Ib eza, Anders Gunnarssonb, Gwen O riscollb, Olga Shatnyevac, Xabier Osteikoetxead and Niek Dekkerba csingle particle level, employing monomeric EGFP as a reference. Results: The screening of EGFP fused for the N- or Cterminal of EV proteins served as a quantitative strategy to determine protein candidates for the surface display of EV-associated cargo. Fusions to CD47 and luminal EV proteins having a snorkel domain permitted the show of EGFP in the surface of EVs, with CD47 as great candidate for surface display. Alternatively, fusions of EGFP to EV proteins with either C- or Nin topology like Tspan14 and CD63 allowed for loading of EGFP within the EV lumen. Single EV evaluation applying TIRF microscopy enabled the quantification of the average variety of EGFP molecules per single engineered vesicle, which was between 15 and 136 EGFP/ EV depending on the fusion protein. Summary/Conclusion: The screening of EGFP-fusions to EV proteins revealed numerous protein candidates for both surface display and intra-luminal cargo loading in EVs. These PDGFR manufacturer outcomes contribute for the understanding of EV biogenesis and are relevant for exploiting the potential of engineered EVs as drug delivery systems.OS23.Endogenous drug loading of extracellular vesicles applying microbubbleassisted ultrasound Yuana Yuanaa, K.