Biology Reference
In-Depth Information
Figure 1.1 Summary of the most common chitosan-blend materials used for the fabrica-
tion of nerve graft devices. In general, basic materials are composed of (A) chitosan in dif-
ferent degrees of acetylation to tailor their rateof biodegradability or chitosan-blendedwith,
for example, polyglycolic acid (PGA) (B), polylactid acid (PLA), or other commonly used poly-
mers. Also, blends of chitosanwithmore than one polymer have been described, for exam-
ple, PGA and PLA (C). Chitosan-based materials can further be modified at their surfaces
which will be in contact to the regenerating neural tissue: extracellular matrix
glycoproteins-like laminin (D) or laminin-derived peptides can be added as an collagen
(E) or diverse neurotrophic factors (F), like NGF, GDNF, CNTF, or NT-3. The inner surfaces
of theguidance channels canbemanufactured to allowseedingof regeneration-supporting
cell types, like aligned Schwann cells (G) or different types of stem cells (H). Finally, the inno-
vative electrospinning technique can be utilized to secondary structure the surface of the
chitosan-based materials by adding oriented nano- or microfibers (I).
neurons and glial cells. Yet, experimental results obtained from several ani-
mal models
in vivo
and first data from the first few clinical studies which were
done so far have shown that chitosan-based scaffolds are good candidates for
developing innovative devices for neural repair of both the CNS and PNS.
