Recent advances in 3D printer technology have made it cheap, marketable and popular to use. The scientific community has capitalised on this technology to print everything from blood vessels, heart valves, ears and scaffolds to rebuilding whole organs. A group of North American scientists have now used it to produce a model that may benefit people with MS.

In this article, published in the highly prestigious journal, Nature, the scientists describe how they have used 3D printing to produce artificial human axons to study the effects of potential myelin repair therapies.

In MS, the immune system damages the insulating myelin layer on nerve fibres, disrupting the ability of the nerve cells to signal efficiently. There is a considerable push in MS research to find compounds that will restore the myelin layer on nerve fibres. However, one huge hurdle that scientists face in this hunt for the next generation of MS treatments is the expense and time required to test the effect of numerous potential drugs on myelin repair.

Different approach

In the laboratory, scientists currently use various systems to test the effects of medications on myelination. However, these models are limited; whilst some are created from materials that are much sturdier and more rigid than human nerves, such as glass, others use real nerve cells grown in a dish – an impractical method given the high number of different treatments that need to be tested.

The 3D printed “axons”, however, have similar physical and mechanical properties to the axons in the human brain. The scientists have the ability to change the properties of the artificial axons in order to test and discover different aspects of myelination and mimic both healthy and damaged axons.

In order to prove that the 3D printed axons work as a realistic model, the scientists grew cells that produce myelin (oligodendrocytes) in the presence of these artificial axons. The oligodendrocytes were able to adhere to the printed axons and produce myelin that wrapped around them, mimicking the process that occurs in the human brain. The team also found that narrower and stiffer fibres were preferentially coated in myelin in comparison to fibres which were wider but more flexible.

This an exciting use of this ever-improving technology. These 3D printed axons have the potential not only to help scientists make fundamental discoveries about the myelination process, but also to cheaply and rapidly screen large panels of potential drugs, before moving on to human trials.

With thanks to MS Research Australia – the lead provider of research summaries on our website.