High-resolution microscopy makes it possible to look deep into many biological phenomena. However, when applied to tissue or whole organisms, light microscopy is often limited by molecules and pigments that refract or absorb light. Whereas in non-pigmented organisms, tissue clearing helps overcome some of these limitations, removal of poorly soluble pigments in large model organisms has proven challenging.
Florian Raible’s team at the Max Perutz labs, along with Hans-Ulrich Dodt’s group (TU Wien and Medical University of Vienna) and additional collaborators at the University of Vienna, IMP, and IMBA, have now combined and improved existing tissue clearing and depigmentation methods. Their integrated approach is capable of reducing pigmentation in animals as diverse as bristle worms, squid, zebrafish and axolotls, while preserving the integrity of the organism. Combined with confocal or light-sheet microscopy, this allows researchers to visualize structures such as the eyes, brains and even whole animals at high resolution. “We can now visualize neuronal networks and entire nervous systems at the level of the organism, without having to slice the sample into thinner sections for imaging”, says senior corresponding author and group leader Florian Raible.
The method is also compatible with staining techniques that are used to visualize RNA expression or dividing cells. The Raible lab has been researching the development and regeneration of the central nervous system, and hopes to use this method to advance the field: “With our improved method we can now visualize and study how eyes grow and visual systems regenerate”, concludes Florian Raible.
Original publication in Science Advances:
Marko Pende@, Karim Vadiwala, Hannah Schmidbaur, Alexander W. Stockinger, Prayag Murawala, Saiedeh Saghafi, Marcus P.S. Dekens, Klaus Becker, Roger Revilla-i-Domingo, Sofia-Christina Papadopoulos, Martin Zurl, Pawel Pasierbek, Oleg Simakov, Elly M. Tanaka, Florian Raible@, Hans-Ulrich Dodt: A versatile depigmentation, clearing and labeling method for exploring nervous system diversity. Science Advances