Ial intercellular vehicle for reprograming target cells. Signature of mRNA contents inside cancer exosomes may have clinical applications for diagnostic and therapeutic purposes.omics, mode of secretion and uptake mechanisms. However, in particular the trafficking of EVs in vivo is still poorly understood. Strategies: We here generated the tetraspanins CD63 and CD81 C-terminally fused to a snorkel tag that adds an additional transmembrane domain for the 4 existing ones to become capable to attach further tags facing the extracellular space. Resulting from their extravesicular orientation, these tags may be applied as a future tool to understand trafficking of EVs in vivo. As a initial step we aimed to give proof of principle that our constructs allow to track and isolate functional recombinant EVs from cultured cells. We hence established a technique to isolate functional EVs carrying our recombinant tetraspanins utilizing a mixture of anti-haemagglutinin affinity matrix and Precission protease cleavage to isolate EVs without having damaging the EV membrane and with no losing the CLIP and FLAG tags that are preceding to Precission protease internet site and HA tag. Benefits: Indeed, we were in a position to purify the EVs by this approach. To additional proof that these EVs are able to transfer intact and active cargo to recipient cells, we on top of that loaded the EVs with Cre recombinase mRNA. As a result, we stably expressed recombinant tetraspanins and Cre recombinase in donor HeLa cells and fluorescent colour switch LoxP technique in recipient HEK293 cells. Indeed, snorkel tagged EVs had been taken up LILRA6 Proteins Biological Activity within this experiment. Using an in vivo mimicking 3D cell culture model, we also observed a crosstalk from human dermal fibroblasts to keratinocytes with snorkel tag containing EVs. Summary/Conclusion: Ultimately, we are presently testing if snorkel tag containing EVs from the stable HeLa cell line introduced into a xenograft mouse model could be isolated from plasma and tissues to understand the distribution of tumour derived EVs in different tissues. We therefore pave the ground for working with snorkel-tagged EVs as a beneficial tool to know EV trafficking in vivo.LBS08.06 = OWP3.Role of calcium signalling within the biogenesis of ADAMTS9 Proteins supplier distinct kinds of extracellular vesicles derived in the exact same cell os Lrincz1; Bal s Bartos1; D id Szombath1; D iel Veres1; nes Kittel2; Erzs et Ligeti1LBS08.05 = OWP3.Unravelling the distribution of extracellular vesicles in vivo applying recombinant tetraspanins Stefan Vogt1; Madhusudhan Reddy Bobbili1; Carolina Patrioli1; Samir Barbaria1; Markus Schosserer2; Lucia Terlecki-Zaniewicz2; Elsa Arcalis3; Dietmar Pum3; Severin Muehleder4; Wolfgang Holnthoner4; Christopher Kremslehner5; Florian Gruber6; Johannes Grillari1 Division of Biotechnology, University of All-natural Resources and Life Sciences, Vienna, Austria., Vienna, Austria; 2CDL for Biotechnology of Skin Aging BOKU Division of Biotechnology, Vienna, Austria; 3Department of Applied Genetics and Cell Biology, University of All-natural Resources and Life Sciences, Vienna, Austria., Vienna, Austria; 4Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Analysis Centre, Endothelial Cell Croup, Vienna, Austria., Vienna, Austria; 5Department of Dermatology, Health-related University of Vienna, Austria; Christian Doppler Laboratory for Biotechnology of Skin Aging, Austria., Vienna, Austria; 6 CDL for Biotechnology of Skin Aging Healthcare University of Vienna, Vienna, AustriaDepartment of Physiology, Semmelweis Univers.