Northwestern scientists discover way to replicate brain tissue

Thanks to a new breakthrough from Northwestern’s McCormick School of Engineering, it may be possible for surgeons in the near future to treat many neurodegenerative diseases by inserting healthy neurons into ailing patients.

Using a new biomaterial, scientists may be able to mimic the properties of healthy human brain tissue and “grow” neurons in a laboratory. These lab-grown neurons can then be transplanted into patients with Parkinson’s, Alzheimer’s, and other neurodegenerative diseases. In addition, this biomaterial can be combined with the patient’s own healthy neurons to create personalized treatments.

Much of this research began all the way back in 2018. Dr. Samuel I. Stupp, director of Northwestern’s Simpson Querrey Biomedical Research Center, and his team published a paper that brought to attention special molecules that were said to be “highly dynamic.” These molecules had the ability to travel over long distances and organize by themselves into bundles of nanofibers. These bundles of nanofibers eventually earned the name "superstructures" due to their ability to cover long distances.

Once the researchers discovered means of controlling the self-organization of these molecules, they were able to modify the superstructures that they created, both from a nano-scale and the scale visible to the human eye.

Stupp eventually went on to direct the research group that continued his work with dynamic molecules in 2020. The formation of a new biomaterial created by these superstructures was found to enhance neuron growth due to a molecule in the biomaterial mimicking the protein that activates neural connections. Known as tropomyosin receptor kinase B (TRKB), this protein usually serves as a receptor for many neurotrophins, or growth factors that influence neurons. One of the main neurotrophins that activates TRKB is brain-derived neurotrophic factor (BDNF).

BDNF allows neurons to be more “plastic” by enabling them to form more connections. In addition to plasticity, increased levels of BDNF in the human brain have also been linked to increased sensitivity in the reward-circuit. When observed, however, its past usage as a form of therapy for injuries in the spinal cord has proven to be expensive.

Thus, engineering neurons within a laboratory may be a more affordable alternative to BDNF engineering.

As far as the next steps of this breakthrough are concerned, Stupp has proposed further research in other areas of regenerative medicine, mainly cartilage and heart tissue, by applying new chemical changes to this biomaterial.