Electrifying research: scientists successfully 3D print an active neuronal network

Scientists detect electrical activity in an engineered neuronal network made from "bioinks" of living cellular material and non-living structural support material.

neural network
Scientists used brain cells from rats to 3D print brain tissue comprised of grey and white matter.

Researchers from Monash University Engineering, Australia, have generated 3D-printed neuronal networks that can grow, transmit, and react to nerve signals under controlled laboratory circumstances using "bioinks".

The bioinks are constituted of living nerve cells (neurons) and a scaffold material that supports the biological material. The researchers successfully imitated the anatomical configuration of grey and white matter present in the human brain.

The study spurs further research into the effects of neuronal diseases, drug testing, and potentially, neural cell regeneration. The research findings were published in Advanced Healthcare Materials.

Types of brain cells

The study’s biological material included astrocytes and cortical neurons from the brains of rats. Astrocytes are a kind of glial cell that provides structural support, they manage nutrient delivery, blood flow, neurotransmitter levels, and ion balance in the brain.

Cortical neurons, on the other hand, are highly developed brain cells that are found in the cerebral cortex and are in charge of more advanced cognitive processing, emotions, sensory processing, motor control, and behaviour.

They support the nervous system in processing and communicating information through the transmission of electrical and chemical signals. Cortical neurons handle information processing, while astrocytes make sure the brain's microenvironment is favorable for optimal neuronal activity.

Grey and white matter

Grey matter contains a high concentration of neuronal cell bodies and is responsible for processing information. The grey also contains dendrites, which are finger or tree-like projections that interact and communicate with nearby neurons.

White matter is primarily made of myelinated axons or nerve fibers that link up neurons into functional circuits. The term myelinated means that the nerve is covered in an insulating layer made up of fatty substances and protein. The white matter is responsible for communication and the insulating layer around the nerve fibers contributes to effective electrical signal transmission.

The researchers found that neurons in the engineered grey matter were actively growing through the white matter tissue, using it as an interface to communicate with other neurons in other layers.

Electrifying results

Sensitive electrophysiological measurements were made as part of the study to confirm spontaneous nerve-like activity in 3D neural networks and to induce reactions to electrical and pharmacological activation. Detecting electrical activity represents a significant development in both neuroscience and bioprinting.

Bioprinted 3D brain structures show potential as a platform for studying neuron and network formation, studying the effects of diseases on neurotransmission, and evaluating pharmacological effects on neurons and the nervous system.