NANOTECHNOLOGY AND 3D BIOPRINTING FOR NEURAL TISSUE REGENERATION - 3D Bioprinting and Nanotechnology in Tissue Engineering and Regenerative Medicine - page 317

FIGURE 14.12
3D bioprinting a nerve graft. Red indicates bone marrow stem cell units, green are the cylinders composed of
90% bone marrow stem cells and 10% Schwann cells, and grey are removable agarose rods. The last picture is
the cross-section view of the printed graft (Schwann cells were labeled as green color). Images are adopted from
Owens et al. (2013) . A color version of this figure can be viewed online.
14.4 CONCLUSION AND FUTURE DIRECTIONS
This chapter reviewed recent advancements with regards to the use of nanotechnology and 3D bioprint-
ing as novel tools to fabricate bioactive constructs for improved neural regeneration. The intrinsic merit
of nanotechnology to regenerative medicine is its high capacity to mimic the physical and chemical
properties of natural ECM. A variety of self-assembling nanomaterials, carbon nanobiomaterials, and
electrospun nanofibers currently under investigation can not only provide a suitable nanoscale envi-
ronment for neural cell adhesion and growth, but also direct neural tissue repair and regeneration via
topographical or chemical guidance. In addition, 3D bioprinting is an excellent approach for the fabri-
cation of patient-specific complex neural grafts where various bioactive factors and cells can be readily
incorporated and synergistically employed for improved neural regeneration.
Despite the vast improvements of nanotechnology and 3D bioprinting in neural tissue engineer-
ing, the development of ideal neural grafts is still in its infancy. Currently, grafts lack the capacity to
bridge defects greater than 30 mm as well as address patients who suffer multiple traumatic injuries
( Marquardt and Sakiyama-Elbert, 2013 ). In addition to spatial guidance of 3D neural constructs, con-
trollable temporal release of growth factors is encouraged for future research. Moreover, current 3D
bioprinting techniques also face many challenges and their ultimate success for neural applications
largely relies on the development of suitable biomaterials to be used as “inks” for the fabrication of
robust neural tissue. Although various traditional biomaterials have continued to be improved, they
have been limited by inadequate biomimetic properties that cannot satisfy the strict requirements of 3D
bioprinting for neural tissue regrowth. It is ideal to integrate 3D bioprinting and biologically inspired
nanobiomaterials that mimic native cellular and ECM for a next generation of neural tissue repair and
regeneration.