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They look more like abstract paintings than the cutting of science.

However, these stunning images are in fact the nerves endings of mice.

It will allow researchers to see individual hair follicles around a nerve ending, for example - and will boost research into nerve disorders.  

This image reveals how touch works. When something brushes a mouse's skin, or the temperature around it changes, this bundle of nerves relays that information from touch receptors on the skin to the spinal cord and ultimately the brain, where it can be processed and acted upon. Shown in green are neurofilaments, in blue isolectinB4 and in red the nerves.

The resulting images show individual nerves, touch receptors, and hair follicles stained in brilliant fluorescent colors that look more like abstract art than cutting-edge microscopy. 

The work, published in Nature Methods, enables researchers to easily use artificial tags, broadening the range of what they can study and vastly increasing image resolution.

'Already we've been able to see things that we couldn't see before,' says Paul Heppenstall from the European Molecular Biology Laboratory (EMBL) in Monterotondo, Italy, who led the research.

'Structures such as nerves arranged around a hair on the skin; we can now see them under the microscope, just as they were presumed to be.'

The technique, called SNAP-tagging, had been used for about a decade in studies using cell cultures – cells grown in a lab dish – but Heppenstall's group is the first to apply it to neurons in living mice. 

It allows researchers to use virtually any labels they want, making it easier to overcome the challenges that often come with studying complex tissues and animals. 

To study nerves in the skin, for instance, Heppenstall's lab can employ artificial dies that are small enough to cross the barrier posed by the skin itself, and stand out better from the skin's natural fluorescence. 

And because these are artificial, custom-made tags, they can be designed to do more than just highlight particular structures. 

Scientists can produce tags that destroy certain structures or cells, for instance.

SNAP-tagging relies on a small protein that binds to a specific small chemical structure – and once bound, it won't let go. 

The EMBL scientists genetically engineered mice so that their cells would produce that SNAP protein. 

The approach showed that free nerve endings (red) in the skin split into many branches. 'This is my favorite image – we'd never seen anything like this until we used this technique,' says Heppenstall. 'It shows that free nerve endings [red] in the skin split into an incredible number of branches.' Labelled in blue are the nuclei of the skin's cells.

The nerves (red) that branch into a 'basket' of endings around the base of each hair (thick blue line), shown in unprecedented detail.

They then used fluorescent probes that contain the small chemical that SNAP binds to, and injected them into the mice. SNAP acts like an anchor, glueing the tags in place for researchers to follow under the microscope.

Ultimately, Heppenstall aims to employ this approach to record activity in individual neurons. 

For instance, he'd like to mechanically stimulate the skin, or change its temperature, and watch that information flow through the nerve, to the next nerve, tracking it throughout the whole network. In principle, he speculates, you could do this in a whole brain. 

It would be like a taking a scan and zooming in to see what's happening inside each nerve cell.

Researchers can now use custom-made artificial labels, obtaining much more detailed images of the skin's nerves.

Previous approaches using labels that relied on antibodies had difficulty penetrating the skin