Biophysical Society Thematic Meeting | Ascona, Switzerland

Liposomes, Exosomes, and Virosomes: From Modeling Complex Membrane Processes to Medical Diagnostics and Drug Delivery

Poster Abstracts

56-POS Board 28 Dissecting Exosome Biogenesis and Uptake via Anthrax Toxin Oksana A. Sergeeva 1 , Katrin Volkmann 2 , Laurence Abrami 1 , Prisca Liberali 2 , Gisou Van der Goot 1 . 2 Friedrich Miescher Instittue, Basel, Switzerland. 1 Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland, Exosomes are endosomal vesicles that can be trafficked from cell to cell. While they have been implicated in a variety of diseases and linked to biomarkers, understanding how exosomes are made from cells, let alone from diseased cells, has been a challenge. Because most laboratories use specific purification techniques and cell types to study exosome biogenesis and uptake, little is known about general exosome endogenous properties. Recently, we found that lethal factor (LF) of anthrax toxin can be transferred to naïve cells via exosomes. Usually, LF enters the cell using protective antigen and anthrax receptors and then eventually makes its way into the cytoplasm, where it can cleave MAPKKs and cause apoptosis. Using anthrax toxin as a tool allows us to observe and probe exosome biogenesis and uptake without purification of the exosomes or major perturbations. We are investigating what genes and factors are required for exosome biogenesis and release from primary cells and then uptake by naïve cells. We have been screening a thousand genes that may be implicated in the exosome pathway for their involvement, and are following up on the most interesting candidates. Additionally, we are unraveling the mechanism behind ER stress and GPI-anchored proteins playing a role in exosome uptake. Overall, we are gaining general knowledge of exosome biology via our unique system, which can then be used to address exosome biomarkers and disease.

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