The world's first see-through mouse
Scientists have found a way to make animals bodies transparent, revealing connections between cells and fine-grained cellular structures, in what is expected to be a boon to biomedical research. The process could lead to more accurate clinical diagnoses and disease monitoring, and a new generation of therapies for conditions ranging from autism to chronic pain, its inventors say.
It “has the potential to accelerate any scientific endeavour that would benefit from whole-organism mapping, including the study of how peripheral nerves and organs can profoundly affect cognition and mental processing, and vice versa”, says senior study author Viviana Gradinaru of the California Institute of Technology.
“Tissue clearing”, as the process of making organs and tissue biopsies transparent is called, has been around for 100 years. But Gradinaru believes this study is the first to perform whole-body clearing, “as opposed to first extracting and then clearing organs outside the adult body”.
The new process allows researchers to build three-dimensional maps of intact organs and bodies, crucial for understanding complex, long-distance cellular interactions.
The research builds on a technique dubbed CLARITY, which Gradinaru and her collaborators previously developed for brain-clearing. It involves embedding tissue into hydrogels to preserve its 3D structure and important molecular features. Detergents are then used to extract lipids that make the tissue opaque.
In the new study, published in Cell, the researchers set out to make CLARITY suitable for whole organs and bodies, in part by making the process faster.
“Our easy-to-use tissue clearing protocols, which employ readily available and cost-effective reagents and equipment, will make the subcellular interrogation of large tissue samples an accessible undertaking within the broader research and clinical communities," Gradinaru said.
Cell has a Q&A interview with Dr. Gradinaru here.