Multifunctional Neural Guidance Devices for Stem Cell Regeneration

This interdisciplinary project will study the design of microdevices based on carbon nanotube fibers (CNF) for the growth and transplantation of neural stem cells into the injured central nervous system. Recovery of function is possible when axons regenerate and are remyelinated.  Cellular transplant therapies represent exciting possibilities to facilitate these processes but the environment after injury is highly disorganized and microdevices to support cells may be important for optimizing transplant efficacy. 

Fig. 16. Electrical contact pins are engineered to foster long-term connectivity with engineered neural tissue derived from stem cells that are capable of integrating into existing neural networks.  A motor command from the brain would be carried to input pins above the injury and translated via a computer interface to the motor neuron contact pins below the injury.

Microdevices based on CNFs may be advantageous because CNFs are stable, porous fibers that support cell adhesion.  Trainees in the Neimark laboratory (CBE) will fabricate CNF from single wall carbon nanotubes with a polymer binder in the form of flexible "hair-like" fibers and study the adhesion and growth of rodent neural stem cells called “radial glia”, which promote functional recovery after spinal cord injury. The porous core of the CNF may be particularly advantageous for controlling more uniform cell growth and differentiation in contrast to the widely used “neurospheres".  In vitro experiments by IGERT Trainees will optimize cell growth and differentiation in the Plummer lab (CDB) and potential cellular devices will be transplanted into the contused spinal cord to evaluate axonal regeneration and functional recovery in injured rats in the Grumet lab (CDB). The permeable microfluidic conduits and electrically conductive properties of the CNF may extend the utility of implantable CNF-cellular devices.  One such implantable device design to be explored by IGERT Trainees would involve the possible incorporation of engineered stem cells for the dual purpose of integration into neural tissue coupled with the ability to sustain contact with molecules coated onto synthetic surfaces (Fig. 16).