Biology Reference
In-Depth Information
In addition, biodegradable chitosan microgrooved polymers were suc-
cessfully used to align Schwann cells (SCs) and cells of the glial cell line
C6. SCs display high degree of alignment and express neurotrophic factors,
like glial-derived neurotrophic factor (GDNF) and nerve growth factor
(NGF;
Hsu, Lu, Ni, & Su, 2007
). Yuan et al. also reported that chitosan
membranes and fibers have excellent neuroglial cell affinity and good bio-
logical compatibility. SCs grown on chitosan membranes displayed a spher-
ical shape, whereas on chitosan fibers, they had an elongated morphology
(
Yuan et al., 2004
). Yet,
Wang et al. (2009)
reported that a chitosan non-
woven nanofiber mesh tube with an inner layer of oriented nanofibers, pro-
duced by electrospinning method, induced alignment of immortalized adult
mouse SCs (IMS32).
Cells of the rat SCs line RT4-D6P2T cultured on PCL/chitosan blend
nanofibrous scaffold showed higher cell proliferation in comparison with
cells grown on PCL scaffolds alone and maintained their characteristic cell
morphology, with spreading bipolar elongation (
Prabhakaran et al., 2008
).
Interestingly, culturing adult rat SCs on chitosan films with low acetylation
resulted in better cell spreading and proliferation (
Wenling et al., 2005
).
Cross-linking agents may also influence the adhesion and proliferation of
cultured SCs.
Cao et al. (2005)
showed that HDI cross-linked chitosan films
enhanced the spread and the proliferation of SCs, whereas ECH and GA
cross-linked films delayed cell proliferation.
Electrical stimulation, through conductive polymers, can be used to
enhance neurite outgrowth and peripheral nerve regeneration. Conductive
polypyrrole chitosan membranes have been shown to support SC adhesion,
spreading with and without electrical stimulation (
Huang, Hu, et al., 2010
).
Interestingly, this study provides confirmation of cell biocompatibility on
chitosan conductive polymers.
Concerning employability of chitosan for neural repair,
in vitro
studies
using neural stem cells (NSCs), human adipose-derived stem cells
(hADSCs), neuroepithelial stem cells (NEPs), and iPS cells have been carried
out since these cells have a great potential as a cell replacement therapy
for SCI.
Chitosan/collagen membrane showed low cytotoxicity supporting rat
NSC (at the neurosphere level) survival, proliferation, and differentiation.
In particular, cells migrate out from the neurospheres and differentiate into
neurons (
Yang, Mo, Duan, & Li, 2010
). NSCs have been also cultured on
laminin-coated chitosan channels (
Guo et al., 2012
).
