Tissue engineered, guided nerve tube consisting of aligned neural stem cells and astrocytes

Injury of the nervous system, particularly in the spinal cord, impairs the quality of life of the patient by resulting in permanent loss of neurologic function. The main limitation in spinal cord regeneration is the lack of extracellular matrix to guide nerves for functional recovery of the transected nerve tissue. In the present study, a tissue engineered nerve tube was prepared by wrapping neural stem cells (NSCs) on aligned fibers using a micropatterned film with astrocytes aligned along the microgrooves to support the NSCs. Initially the cell behavior on micropatterns and parallel fibers was investigated with cytoskeletal and nuclear staining, immunocytochemistry, and proliferation assay using the fiber and the film system separately. The results showed that both cells, NSCs in undifferentiated and astrocytes in differentiated form, were oriented in the direction of the guiding and support elements, the microgrooves, and the microfibers. They were able to grow and increase in number on these cell carriers. This trend was also maintained after the components were brought together in a nerve tube form and testing in coculture. The cells were able to survive and maintained their orientation in the 3D tissue engineered construct. The guided nerve tissue engineering approach tested in the present study with parallel NSCs and support cells in the tubular construct is expected to provide an appropriate environment for nerve regeneration in vivo.