Kwanghun Chung wants to make it easy for scientists to take a molecular snapshot of the brain. The very best imaging technology available today allows inspection of just 10 or so biomolecules in 3-D. \u201cIt\u2019s not enough,\u201d says Chung, who hopes to render a complete picture of all of the hundreds of thousands of biomolecules at work inside the thousands of distinct cell types across a whole human brain.<\/p>\n
A new assistant professor in MIT\u2019s Department of Chemical Engineering, Chung started on a project to preserve subsets of neurons in brain samples and to isolate them in place for visualization while a postdoc at Stanford University.<\/p>\n
His proposal to preserve all the cells and, at the same time, make them transparent and permeable led to the development of CLARITY. This method shores up postmortem brain tissue using a chemical mesh and then dissolves all of the fat, which is what previously made it so hard to see into the brain. What remains is a transparent \u2014 yet perfectly intact \u2014 brain.<\/p>\n
With the aid of molecular and structural markers, it is possible to take a visual voyage deep inside the \u201cclarified\u201d brain and see the structures, connections, individual neurons, and molecules at work inside them. \u201cThe good thing about CLARITY is that it\u2019s not destructive,\u201d Chung says. \u201cYou can use it over and over again, adding and removing molecular probes until you extract out all the information you want.\u201d<\/p>\n
During development of CLARITY, Chung was influenced by two of his colleagues, who shared with him their personal stories about siblings with autism. \u201cI realized the impact brain disorders have on people\u2019s lives and decided to focus my research on mapping the human brain,\u201d he says. \u201cThere is huge room for neurotechnology development that can significantly accelerate the pace of discovery and the development of new therapeutics.\u201d<\/p>\n
As a participating researcher with MIT\u2019s Institute for Medical and Engineering Science, Chung believes he is especially well positioned to continue on this path.<\/p>\n
\u201cThrough IMES, I can collaborate with engineers, neuroscientists, and doctors who see patients with brain disorders,\u201d says Chung, who is also a principal investigator at the Picower Institute for Learning and Memory.<\/p>\n
In his new lab, Chung is working to make CLARITY scalable to human brains. His other main focus, in collaboration with researchers at the Broad Institute, is on extracting a complete collection of molecular information from intact three-dimensional brain tissue, a project akin to his earlier microfluidic embryo and cell trackers, only at a billion or so times the scale.<\/p>\n
\u201cEngineers really need to jump in with scientists and clinicians,\u201d Chung says. \u201cWe need to work together to develop new tools to crack the brain.\u201d<\/p>\n