Successful CLEM Course in Tromsø

Tromsoe sebFor 10 days scientists were gathered at the University of Tromsø for the specialized course in Correlative Light and Electron Microscopy (CLEM): 13 students and 11 instructors!


rat intestine

CLEM is the fusion of light microscopy with electron microscopy on the same sample. Here, a section of rat intestine was stained for a specific protein (beta-Catenin, yellow in top image). A specific region was then picked out and the precise localization of the protein was studied in the electron microscope (black dots in bottom image). Photo modified from Schwarz and Humbel, Methods Mol Biol 2007.

Through lectures and practical testing, PhD students and post-docs got a chance to dig deeper into the worlds of light and electron microscopy. Being an active user of both techniques, I was thrilled to learn more about how a single sample can be prepared for both methods in conjunction, thereby giving much more information than each of the methods could provide alone.

The course, which took place at the University of Tromsø on January 7-16, was organized by the Department of Medical Biology (UiT), in collaboration with the Norwegian Research School in Medical Imaging - MedIm. The course attendants ranged from fresh PhD students with little background in microscopy, to experienced PhDs and postdocs that wanted to learn more about the technical details of CLEM.



Top: Heinz Schwarz (Max Planck Inst for Dev Biol, Tübingen)
talks about the preparation of samples to Stian Olsen (behind

Schwarz), Mehrdad Sobhkhez, Samuel Geiseler and Sebastian

Schultz. Bottom: Yannick Schwab (The European Mol Biol
Lab, Heidelberg) instructs Hallvard L.Olsvik in cutting of ultrathin
sections for CLEM. Sebastian Schultz is taking notes

What was so special about this course? The instructors, CLEM specialists from Germany, France, Oslo and Tromsø, stayed for the full length of the course and participated in all lectures, demonstrations and practical exercises. This gave the students many chances for valuable one-on-one discussions with the instructors. Furthermore, since all the instructors were present throughout, the course got a better flow and unnecessary repetitions or holes in the curriculum were avoided. A similar approach is used in the popular hands-on courses arranged by EMBO and Cold Spring Harbor Laboratories. Organizers Bård Smedsrød, Karen Sørensen, Randi Olsen and Kenneth Bowitz Larsen at UiT were pleased with how the course went down. Sørensen added that as instructors, they also learned a lot: “We always pick up useful information from each other’s talks and demonstrations”, she said.

After 10 intense days, our brains were full with new information and we were eager to test out everything we had learnt. Following a demonstration of freeze substitution, postdoctoral fellow Sebastian Schultz commented: “I am ready to go back and do this in the lab on Monday. This demo shows you all these little tricks that you just can’t read about in a paper.”


IMG 0094 HPF1

Top: Jørgen Benjaminsen (Dept of Biosciences, University of Oslo) demonstrates high pressure
freezing, a method to quickly fix the tissue in a way that “freezes” proteins and cell membranes in
their natural position. Bottom: Yannick Schwab shows and discusses the technicalities of
freeze substitution.Top right and bottom photos by Samuel Geiseler

Photo top left by Sebastian Schultz

By Johanne Egge Rinholm for Nansen Neuroscience Network