Brain clarity

Rodent brain with fluorescently-labelled proteins

Researchers at Stanford University have pioneered a technique that will greatly enhance our understanding of the structure of the human brain.

In the past scientists have relied on the slicing technique to build a 3 dimensional view of the brain.  Although this is a great improvement on previous post-mortem study it is still ultimately very destructive.  The slicing operation destroys intricate structures before they can be studied.

The Stanford research project, code named CLARITY keeps the entire organ intact.  Previous work that sought to remove the lipids (fatty molecules) from the brain was fraught with problems as the structures literally fell apart as the lipids were drained.  CLARITY submerges the post-mortem brain in a hydrogel solution that penetrates every nook and cranny of the organ to preserves the delicate brain structure.  When the hydrogel is raised to normal body temperatures it sets to form a fine mesh that reveals the intricate structures in all their glory.  A technique called electrophoresis (separation using electrically charged particles) is employed to rapidly remove the fatty molecules once the mesh has formed.

The technique is so good that individual neural connections are kept intact, allowing for an unprecedented level of detailed study to take place.

Fluorescent antibodies provide amazing clarity of the organ

With the brain preserved by the hydrogel mesh the real magic can now begin.  Using antibodies with fluorescent properties that attach to specific structures the scientists can illuminate the area with an unbelievable level of clarity.

To date the research has focused on rodent and fish brains with some human samples also tested but the team hope to test the technique on a whole human brain in the near future.

This is certainly a project to watch with great interest.

Read the full paper in Nature or check out the Stanford media release.

Clearer views of the brain (Guardian UK)

See through brains (PopSci)