Dynamic super-resolution structured illumination imaging in the living brain

Abstract

Cells in the brain act as components of extended networks. Therefore, to understand neurobiological processes in a physiological context, it is essential to study them in vivo. Super-resolution microscopy has spatial resolution beyond the diffraction limit, thus promising to provide structural and functional insights that are not accessible with conventional microscopy. However, to apply it to in vivo brain imaging, we must address the challenges of 3D imaging in an optically heterogeneous tissue that is constantly in motion. We optimized image acquisition and reconstruction to combat sample motion and applied adaptive optics to correcting sample-induced optical aberrations in super-resolution structured illumination microscopy (SIM) in vivo. We imaged the brains of live zebrafish larvae and mice and observed the dynamics of dendrites and dendritic spines at nanoscale resolution.

Imaging of the immune system – towards a subcellular and molecular understanding

“…In super-resolution imaging (∼50 nm resolution), cells, cell processes or tracked molecules that move faster than 50 nm per acquisition frame will not be imaged accurately. Thus, faster super-resolution imaging techniques, such as SIM (at least 9.3 Hz) (Turcotte et al, 2019) Fig. 3.…”

Full three-dimensional imaging deep through multicellular thick samples with subcellular resolution by structured illumination microscopy and adaptive optics

“…Its fast response allows the deformable mirror (DM) to be adjusted for every image frame when imaging dynamic processes in live samples. Turcotte et al [34] reported a combination of 2D SR-SIM (increased lateral resolution and optical sectioning) and direct wavefront sensing AO to image the dynamics of dendrites and dendritic spines in the living mouse brain in vivo. However, the direct wavefront sensing method requires a dedicated wavefront sensing system (e.g.…”

3D super-resolution deep-tissue imaging in living mice

“…Using these displacements, the SHS can reconstruct the wavefront, determine its constituent Zernike modes and thus the corrective phase that needs to be added to the system. This approach to aberration correction has been used to recover the optimal resolution of 2PE laser scanning [27,28] and structured illumination [29,30] microscopes deep in tissue, including in a living mouse [30,31].…”