Researchers are making progress on the construction of cell structures that look very much like naturally formed nerve tissue, and may thus be useful substitutes for the current practice of nerve grafting:
Regeneration of nerves is challenging when the damaged area is extensive, and surgeons currently have to take a nerve graft from elsewhere in the body, leaving a second site of damage. Nerve grafts contain aligned tissue structures and Schwann cells that support and guide neuron growth through the damaged area, encouraging function to be restored.
[Researchers have now] reported a way to manufacture artificial nerve tissue with the potential to be used as an alternative to nerve grafts. Pieces of Engineered Neural Tissue (EngNT) are formed by controlling natural Schwann cell behaviour in a three-dimensional collagen gel so that the cells elongate and align, then a stabilisation process removes excess fluid to leave robust artificial tissues. These living biomaterials contain aligned Schwann cells in an aligned collagen environment, recreating key features of normal nerve tissue.
Building the artificial tissue from natural proteins and directing the cellular alignment using normal cell-material interactions means the EngNT can integrate effectively at the repair site. "We previously reported how self-alignment of Schwann cells could be achieved by using a tethered collagen hydrogel, which exploited cells' natural ability to orientate in the appropriate direction by using their internal contraction forces. Our current research shows that cell-alignment in the hydrogel can be stabilised using plastic compression. The compression removes fluid from the gels, leaving a strong and stable aligned structure that has many features in common with nerve tissue."