Was dependent on the presence of functional viral Env machinery,ISEV2019 ABSTRACT BOOKeither from actively circulating viruses including VSV-G, rabies, influenza, and mokola viruses or from human endogenous retroviruses (HERVs) Env proteins such as syncytin-1. Summary/Conclusion: EVs created within the absence of viral Env machinery are poorly fusogenic and are unlikely to become efficient mediators of cell-tocell communication via the delivery of EV contents to the cytoplasm. In contrast, viral Env proteins substantially improve EV fusogenicity, suggesting that EV fusion and communication might occur and play a important role throughout viral infections. In addition, cells expressing the HERV Env syncytin-1 such as lots of human cancers also give rise to fusogenic EVs that may contribute to tumour establishment, growth, and metastasis. These findings suggest that blocking syncytin-mediated EV fusion might be an efficient approach to block EV communication in human cancers.OS24.Preferential accumulation of copper-free click chemistry-modified exosomes to personal pancreatic xenograft in vivo Lizhou Xua, Revadee Liam-Orb, Farid N. Faruqub, Omar Abedc, Danyang Lib, Julie Wangb and Khuloud Al-Jamalba School of Cancer and Pharmaceutical Sciences, King’s College London, London, UK; bKing’s College London, London, UK; cKing’s College London, London, UKResults: Cellular uptake of Exo was time- and dosedependent profiles. Computer derived PANC-1 Exo showed substantially higher and not saturable uptake in PANC1 cells compared to B16-F10 Exo (cancer-derived) and HEK-293 Exo (non-cancer derived) which showed lower and saturable uptake profile at 24 h. In vivo biodistribution research of PANC-1 Exo in subcutaneous Pc xenograft additional confirmed that PANC-1 Exo favoured accumulation in Computer tumours over melanoma (B16-F10) tumours. Summary/Conclusion: A very simple and highly efficient surface modification strategy via click chemistry was developed enabling both in vitro and in vivo tracking of Exo. DoE modelling predicted Computer cells’ preference to PC-derived Exo which was confirmed also in vivo. This Exo dosimetry study could facilitate a rationalized approach in Exo-based therapeutics for therapy of cancer in pre-clinical research. Funding: The K. C. Wong Education Foundation and the Marie Sklodowska-Curie actions, European Commission “Horizon 2020”, EU (H2020-MSCA-IF2016)OS24.Particular transfer of hollow gold nanoparticles inside exosomes is determined by the exosome origin Maria Sancho-Alberoa, Nuria Navascu b, Gracia Anti-Muellerian Hormone Type-2 Receptor (AMHR2) Proteins Synonyms Mendozab, Victor B7-H3/CD276 Proteins manufacturer Sebastiana, Manuel Arrueboa, Pilar Martin-Duquec and Jesus SantamariaaaIntroduction: Pancreatic cancer (Pc) is among the deadliest malignancy with few powerful approaches out there for early diagnosis or therapy. Exosomes (Exo) as 1 form of extracellular vesicles are currently being investigated as possible theragnostic tools in cancer. However, it really is not yet well-understood how Exo are taken up by Pc cells. This function aims to study the Exo dosimetry and preferential Exo-cell affinity in Pc cells in vitro and in vivo for exploitation of Exo-based delivery of therapeutics. Approaches: Exo are isolated by sucrose cushion ultracentrifugation and characterized for exosomal marker expression, quantity, purity and shape. Exo were fluorescently labelled by copper-free click chemistry to enable uptake quantification in cells making use of the Style of Experiments (DoE) approach. Cellular uptake of Exo was investigated applying flow cytometry and confocal microscopy. Fa.
