Whole Brain Mapping of Primates Enters Micron Era

The research team of Prof. Guo-Qiang BI and Prof. Pak-Ming Lau from University of Science and Technology of China (USTC) and Shenzhen Institute of Advanced Technology (SIAT) of the Chinese Academy of Sciences, along with domestic and international collaborators, realized three-dimensional mapping of the entire brain of the macaque monkey at micron resolution, based on an updated version of their recently developed high-throughput three-dimensional fluorescence imaging technique VISoR, and an efficient pipeline SMART. This work is published in Nature Biotechnology on July 26th.   Our brain comprises nearly a hundred billion nerve cells with delicate and complex connections among them. To fully understand how the brain functions, it is essential to have a high-resolution map of how the nerve cells are organized and connected within the brain. At present, it usually takes days to complete three-dimensional imaging of the whole brain of a mouse at micron resolution using the current state-of-the-art techniques.   However, high-resolution brain mapping for nonhuman primates such as the rhesus monkey, although highly desired given their roles in modeling human diseases, has been hindered by a major technical challenge. The brain of a rhesus monkey is too big, more than 200 times larger in volume than that of a mouse.   To overcome this challenge, the team developed a high-throughput three-dimensional fluorescence imaging technique, Volumetric Imaging with Synchronous on-the-fly-scan and Readout, VISoR. Compared to commonly used 3D optical imaging techniques, VISoR eliminates the time loss caused by moving and pausing while switching fields of view to obtain 2D image series, allowing for imaging without blur when the sample is in continuous motion. In this way, VISoR achieves extremely high speed, dozens of times faster than other 3D imaging methods for large tissue samples.