(56g) Fusion of Outer Membrane Vesicles: Surface-Display of Different Epitopes on a Single Vesicle
AIChE Annual Meeting
2017
2017 Annual Meeting
Nanoscale Science and Engineering Forum
Bionanotechnology for Gene and Drug Delivery II
Monday, October 30, 2017 - 9:48am to 10:06am
To approach this challenge a different way, we considered membrane fusion, a process through which phospholipid bilayers, from identical or different structures, mix, collapse, and ultimately form a single bilayer. Through the fusion of OMVs, it is possible to achieve the surface-display of multiple different epitopes types on a single OMV surface. In this study, we show that fluorescently-labelled OMVs made from engineered Escherichia coli Nissle 1917, described in one of our previous studies [4], are capable of fusing under controllable conditions. Acidic pH and the presence of divalent cations such as Ca2+ and Mg2+ in the suspension tune the colloidal properties of suspended OMVs as well as modulate OMV aggregation and fusion kinetics. Quantitative measurements of the kinetics of the OMV bulk fusion show that the maximum fusion efficiency is increased with decreasing pH and increasing salt concentration but is fusion-limited at high salt concentrations, where particle aggregation begins to dominate.
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