Harald HESS: 3D Imaging of Cells by FIBSEM with Correlation to Cryo Fluorescence Microscopy


Event details

Date and time 24.06.2021 17:0018:00  
Online https://epfl.zoom.us/j/83704327175
Speaker Harald Hess, HHMI’s Janelia Research Campus, USA 
Category Conferences - Seminars
This event is part of the EPFL Seminar Series in Imaging (https://imagingseminars.org).

Abstract. 3D electron microscopy data can be acquired by Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) where fine sequences of 4-8 nm increments are ablated off of a sample surface and each such surface is imaged with the SEM. At the finest resolution and with month-long stable operation, comprehensive whole cells can be acquired that transcend the limited cut section views of traditional TEM used in biology.

Several examples of such data are presented along with the potential that segmentation offers to explore and formulate biological questions. Correlative microscopy can be achieved by a cryogenic protocol where samples are vitrified, imaged with PALM or SIM at low temperatures followed by EM staining and FIBSEM.  A 3D registration procedure can keep most position errors between PALM and EM data at ~ 30 nm.  Examples validating the approach with mitochondrial and endoplasmic reticulum labels are presented along with examples showcasing how unknown vesicle types and other structures can be identified by an associated protein.

Biography. Harald Hess is a senior group leader at HHMI’s Janelia Research Campus in the USA. His main interests lie in the development of high-throughput 3D electron microscopy and super-resolution 3D optical microscopy for use in brain connectomics and cell biology.