Creating Supported Plasma Membrane Bilayers Using Acoustic Pressure

Abstract

Model membrane systems are essential tools for the study of biological processes in a simplified setting to reveal the underlying physicochemical principles. As cell-derived membrane systems, giant plasma membrane vesicles (GPMVs) constitute an intermediate model between live cells and fully artificial structures. Certain applications, however, require planar membrane surfaces. Here, we report a new approach for creating supported plasma membrane bilayers (SPMBs) by bursting cell-derived GPMVs using ultrasound within a microfluidic device. We show that the mobility of outer leaflet molecules is preserved in SPMBs, suggesting that they are accessible on the surface of the bilayers. Such model membrane systems are potentially useful in many applications requiring detailed characterization of plasma membrane dynamics.

Pore-Spanning Plasma Membranes Derived from Giant Plasma Membrane Vesicles

“…To the best of our knowledge, only two different methods have been reported previously to burst pure pdGPMVs to form planar membrane patches on glass substrates. , In both cases, a particular treatment of the surface-adhered pdGPMVs, i.e., an air–water interface compression technique or acoustic radiation forces was required to be able to induce GPMV bursting. Here, we used pdGPMVs and calGPMVs and were able to readily spread them onto oxygen plasma activated SiO 2 surfaces with no additional treatment.…”

“…For supported plasma membranes obtained from pdGPMVs, we obtained diffusion coefficients for R18 of D = 1.0 ± 0.8 μm 2 /s (n = 17), similar to what has been reported in literature. 25,26 Supported plasma membranes derived from calGPMVs show by a factor of 2.5 lower average diffusion coefficient of D = 0.4 ± 0.1 μm 2 /s (n = 16). Interestingly, already the diffusion coefficients of R18 in GPMVs differ dependent on the vesiculation agents.…”

“…Chiang et al 25 were able to rupture pure GPMVs on glass substrates by an air−water interface compression technique. Recently, Sezgin et al 26 applied acoustic radiation forces to burst GPMVs on plasma-cleaned coverslips. To the best of our knowledge, pore-spanning plasma membranes obtained from spreading of GPMVs on porous substrates have not been achieved at all.…”

Model membrane systems to reconstitute immune cell signaling

“…Without doubt, having such valuable tools will allow us to study the effect of checkpoint inhibitors and immune stimulators at a physiological level previously unmatched by synthetic systems alone. For this purpose, the exploitation of native membrane systems such as giant PM vesicles [164] and their adaptation into supported PM bilayers [165] is a mandatory step to unravel the fundamental dynamics of membrane physiology for different phenotypical states.…”

Special Issue: Dynamics and Nano-Organization in Plasma Membranes

“…Sezgin et al [5] reported a novel approach for creating supported plasma membrane bilayers (SPMBs) by bursting cell-derived giant plasma membrane vesicles using an ultrasound microfluidic device. Sezgin et al showed that the diffusion of lipids as well as proteins in these SPMBs in the outer leaflet is preserved, suggesting that these molecules are accessible on the surface of the bilayers.…”