Measuring diffusion exchange across the cell membrane with DEXSY (Diffusion Exchange Spectroscopy).
journal contributionposted on 2020-06-25, 13:51 authored by James O Breen-Norris, Bernard Siow, Claire Walsh, Ben Hipwell, Ioana Hill, Thomas Roberts, Matt G Hall, Mark F Lythgoe, Andrada Ianus, Daniel C Alexander, Simon Walker-Samuel
INTRODUCTION: To combine numerical simulations, in vitro and in vivo experiments to evaluate the feasibility of measuring diffusion exchange across the cell membrane with diffusion exchange spectroscopy (DEXSY). METHODS: DEXSY acquisitions were simulated over a range of permeabilities in nerve tissue and yeast substrates. In vitro measurements were performed in a yeast substrate and in vivo measurements in mouse tumor xenograft models, all at 9.4 T. RESULTS: Diffusion exchange was observed in simulations over a physiologically relevant range of cell permeability values. In vitro and in vivo measures also provided evidence of diffusion exchange, which was quantified with the Diffusion Exchange Index (DEI). CONCLUSIONS: Our findings provide preliminary evidence that DEXSY can be used to make in vivo measurements of diffusion exchange and cell membrane permeability.