The mouse peripheral nervous system with nerve cells farther away from the camera represented in yellow and pink, while nerves closer to the camera are shown in blue tones.
Researchers used an antibody that targets neurons to visualize the entire mouse peripheral nervous system.
Ertürk lab, Helmholtz Munich

For years, researchers have aspired to look under the skin at the organism level, but limitations in available technologies hindered their progress. Now, researchers led by Ali Ertürk, a neuroscientist at the Helmholtz Munich, developed a novel chemical method dubbed wildDISCO that enables whole-body immunostaining using off-the-shelf antibodies.1 

The secret to wildDISCO’s success is a cholesterol-removing compound that extracts the lipid from the cell membranes without disrupting the cell’s structure. “This is kind of a magical chemical,” said Jie Luo, a postdoctoral researcher in Ertürk’s lab who helped develop the method and coauthored the paper. According to Luo, the compound helps standard antibodies penetrate the cells more easily and homogeneously. 

The team first applied this method to map the mouse’s peripheral nervous system. After fixing the mouse’s body, Luo and his colleagues pumped solutions containing the cholesterol-removing molecule, followed by addition of a pan-neuronal marker (PGP9.5) coupled to a fluorescent tag, through the mouse’s circulatory system. The team next made the whole mouse body transparent using a method that Ertürk previously developed.2 Using light-sheet microscopy, they imaged the entire mouse body and then stitched the images together using software to create a 3D representation of the mouse’s peripheral neuronal network. 

The resulting image reveals different levels of the peripheral nervous system, which the team color-coded such that nerves deeper in the animal’s body show up in yellow and pink, while nerves closer to the camera appear in blue tones. This whole-body mapping enabled the team to clearly see how different organs are innervated, revealing connections that may help other researchers better understand the roles of these projections in health and disease states. 

The successful labeling motivated the team to continue validating other antibodies using the technique, said Luo, and it highlighted the potential of wildDISCO for improving researchers’ understanding of complex biological systems.