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Liposomes, Exosomes, and Virosomes: From Modeling Complex
Membrane Processes to Medical Diagnostics and Drug Delivery
Poster Abstracts
91
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.