Introduction to the New Imaging Protocol
An international team of researchers, spearheaded by the Francis Crick Institute in collaboration with the Paul Scherrer Institute, has pioneered a groundbreaking imaging protocol that captures the intricate connections of mouse brain cells with unprecedented precision. This innovative approach, detailed in the journal Nature Methods, leverages the power of X-rays combined with radiation-resistant materials originally developed for the aerospace industry.
Overcoming Traditional Limitations
Traditionally, volume electron microscopy (volume EM) has been the gold standard for visualizing the complex circuitry of nerve cells within the brain. This method involves slicing biological tissue into extremely thin sections, imaging each slice, and reconstructing the images into a 3D structure. While effective, this technique is limited by the need to physically slice the tissue, which can be challenging for larger mammalian brains.
The Power of X-ray Imaging
X-rays offer a significant advantage over electrons due to their ability to penetrate deeper into matter. The research team explored the potential of X-ray imaging to capture the fine details of nerve cells without the need for slicing. By building on standard volume EM sample preparation protocols, they introduced a novel step: embedding the stained tissue in a resin developed for nuclear and aerospace applications. This resin, capable of withstanding high levels of radiation, allowed the samples to endure exposure to billions more X-rays than would be lethal to humans.
Utilizing Synchrotron Technology
The samples were imaged using X-rays at a synchrotron, a large facility that accelerates particles to high speeds, producing intense and coherent X-ray radiation. The specific imaging technique employed, known as X-ray ptychography, achieved a remarkable resolution of 38 nanometers. This level of detail enabled the visualization of multiple elements of the mouse brain’s circuitry, including synapses, dendrites, and axons.
Implications for Brain Mapping
Andreas Schaefer, Principal Group Leader of the Sensory Circuits and Neurotechnology Laboratory at the Crick, highlighted the revolutionary potential of this new protocol. While volume EM has been instrumental in 3D cellular visualization, it faces limitations when mapping neuron connections in large mammalian brains. The new X-ray imaging technique, with its extraordinary resolution, represents a significant step towards the ambitious goal of mapping the mouse brain connectome, which is vastly more complex than that of the fruit fly.
Future Directions and Enhancements
Carles Bosch Piñol, Principal Laboratory Research Scientist at the Crick, emphasized the ongoing efforts to refine this method. The team aims to enhance the field of view and resolution, enabling the study of larger samples and finer details. By integrating X-ray imaging with other techniques, new possibilities emerge for exploring the function of biological tissues, such as the brain.
Collaborative Efforts and Further Research
The project was co-led by Ana Diaz and Adrian Wanner at the Paul Scherrer Institute in Switzerland, in collaboration with the European Synchrotron Radiation Facility and the Electron Microscopy team at the Crick. This collaborative effort underscores the importance of interdisciplinary approaches in advancing scientific understanding.
For more detailed information, refer to the publication: “Nondestructive X-ray tomography of brain tissue ultrastructure” in Nature Methods (2025). DOI: 10.1038/s41592-025-02891-0.
🔗 **Fuente:** https://medicalxpress.com/news/2025-11-ray-imaging-captures-brain-intricate.html