Expansion-Assisted Selective Plane Illumination Microscopy Captures Large and Small Biological Detail

Recent advances in tissue processing, labeling, and fluorescence microscopy are providing unprecedented views of the structure of cells and tissues at sub-diffraction resolutions and near single molecule sensitivity, driving discoveries in diverse fields of biology, such as neuroscience. Biological tissue is organized over a scale of nanometers to centimeters. Harnessing molecular imaging across three-dimensional samples on this scale requires new types of microscopes with larger fields of view and working distance as well as higher imaging throughput. Glaser presents a new expansion-assisted selective plane illumination microscope (ExA-SPIM) that leverages technologies from the electronics metrology industry.

These incredible technologies allow the system to provide diffraction-limited and aberration-free imaging over a large field of view, 85 mm2, and working distance, 35 mm. Combined with new tissue clearing and expansion methods, the microscope allows nanoscale imaging of centimeter-scale samples, including entire mouse brains, with diffraction-limited resolutions and high contrast without sectioning.

Glaser also illustrates ExA-SPIM by reconstructing individual neurons across the mouse brain, imaging pyramidal tract neurons in the macaque motor cortex, and tracing white matter tract axons in human neocortex.

About the presenter
Adam Glaser, Ph.D., joined the Allen Institute for Neural Dynamics in 2021. He works in the multi-scale molecular neuroanatomy group, focusing on developing hardware and software tools for large-scale imaging projects. Prior to joining the institute, Glaser worked as a postdoctoral research associate in the Department of Mechanical Engineering at the University of Washington, where he is now an affiliate assistant professor. There he worked in Jonathan Liu’s laboratory, leading the development of open-top light-sheet microscopy systems for three-dimensional clinical pathology. He earned his doctorate in engineering sciences from Dartmouth College in 2015, and Bachelor of Science degree in mechanical engineering from Tufts University in 2010.