Repairing peripheral nerve injury, especially long-range defects of thick nerves, is a great challenge in the clinic due to their limited regeneration capability. 

Nerve guidance conduits with multichannel structure have shown greatly improved efficiency in enhancing axon extension and guiding directional reinnervation. 

A research team led by Dr. ZHAO Xiaoli from the Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences fabricated a self-forming multichannel nerve guidance conduit, which was based on a degradable shape memory polymer, and realized the rapid self-forming of multichannel conduit by using the characteristics of shape memory materials. 

The study was published in ACS Nano. 

The multichannel conduit was designed as a bilayer structure, consisting of a random fiber layer with shape memory for temperature-controlled deformation and an aligned fiber layer for guiding cell migration and growth. The multichannel lumens provided more space for cell proliferation, migration and nerve tissue regeneration compared with a single-channel conduit with a hollow lumen. The internal surface of the conduit composed of aligned electrospun nanofibers provided topographical cues for cell growth and axon elongation. 

The results showed that the automatic deformation from planar fibrous mat to a permanent tubular shape triggered by physical temperature could realize the uniform loading of cells in the conduit. 

More notably, this multichannel conduit exhibited better performance in terms of neurite outgrowth and the repair of rat sciatic nerve defects. 

The study proposed a novel strategy and method to construct nerve guidance conduit. The integration of the internal lumen structure and the wall structure gave the conduit architectural modifications at both the macro- and nanoscale levels, which has more advantages in guiding nerve regeneration. 

The team believes that it has great potential in peripheral nerve repair to provide a favorable microenvironment for peripheral nerve regeneration. 

Schematic diagram of the fabrication of self-forming multichannel nerve guidance conduit and bridging long peripheral nerve defects (Image by SIAT)

Media Contact: 
ZHANG Xiaomin 
Email: xm.zhang@siat.ac.cn