| AVS 58th Annual International Symposium and Exhibition | |
| Biomaterial Interfaces Division | Monday Sessions |
| Session BI-MoM |
| Session: | Biomolecules at Interfaces |
| Presenter: | Lisa Simonsson, Chalmers University of Technology, Sweden |
| Authors: | L. Simonsson, Chalmers University of Technology, Sweden A. Gunnarsson, Chalmers University of Technology, Sweden M. Kurczy, Chalmers University of Technology, Sweden P. Jönsson, Chalmers University of Technology, Sweden AS. Cans, Chalmers University of Technology, Sweden F. Höök, Chalmers University of Technology, Sweden |
| Correspondent: | Click to Email |
Fusion of lipid vesicles and cells is a natural process which takes place in eukaryotic cells. It is a vital process, since it enables cells’ communication with the outside, both via vesicle content release and through delivery of e.g. membrane proteins to the outer cell membrane. Exocytosis is still not fully understood and although attempts have been done to deliver membrane constituents to supported lipid bilayers, improvement in e.g. efficiency remains. In order to gain a deeper understanding of the mechanism of membrane fusion as well as improve the delivery of arbitrary membrane constituents including complete cell membrane fragments, to supported lipid bilayers, we have in this work developed two novel and powerful techniques.
To mimic exocytosis, we use giant unilamellar vesicles (GUVs) as a model of the cell membrane, cholesterol-DNA[1-3] as a mimic of the SNARE-proteins and small unilamellar lipid vesicles filled with easily oxidized catechol to represent the cellular vesicles. We probe the fusion process using a carbon fiber electrode, detecting the released catechol. By building this advanced but yet controllable model system of exocytosis, we believe that a wide range of studies can be made in order to decipher the process of exocytosis. Future applications are delivery of e.g. membrane proteins to GUVs, as well as for vesicular drug delivery to cells.
In order to deliver membrane constituents to SLBs, we use a controlled bulk flow through a microfluidic channel to move the front edge of a supported lipid bilayer and fuse it with vesicles adsorbed in front of it. The membrane constituents of the adsorbed vesicles are efficiently incorporated into the supported lipid bilayer and can be manipulated in 2D (accumulated and separated) by again using the bulk flow. We show that this method is perfectly compatible with cell membrane fragments derived directly from 3T3 fibroblast cells[4]. The method enables studies of e.g. receptor-ligand interactions as well as membrane protein separation in a native environment.