Biomedical Engineering Reference
In-Depth Information
layering cardiac cell sheets has shown electrical and fully functional
coupling and beats macroscopically [21]. Various cells can be easily
recovered as cell sheets using the temperature-responsive culture
surface and can be transplanted directly onto host tissues without
suturing. The application of cell sheets prepared on this unique
surface to the regeneration of various tissues is described in the
following chapters.
4b.3
The Applications of Cell Sheet-Based
Tissue Engineering for Regenerative
Medicine
4b.3.1
Two Epithelial Cell Sheets for Corneal Surface
Regeneration
Limbal stem cell deficiency from exogenous trauma or endogenous
diseases causes corneal opacification and may finally lead to
blindness. Although corneal graft using donor eyes is used as
the most common therapeutic method, the therapy has several
problems including the shortage of donor eyes and the high risk of
graft rejection. Recently, a novel therapy for improving the visual
acuity of patients using autologous epithelial cell sheets has been
developed [19]. Autologous corneal epithelial cell sheets (in the case
of patients with unilateral disease) or oral mucosa epithelial cell
sheets (for patients with complete bilateral corneal epithelial stem
cell deficiencies) are used in the therapy. These autologous epithelial
cell sheets preserve complete cell-cell junctions and an ECM within
the cell sheet, so the cell sheets adhere rapidly onto the host eye
without suturing and the corneal surfaces are perfectly protected
from fluorescein permeation immediately after the therapy [19, 22].
After transplantation, oral mucosal epithelial cell sheets (1) more
closely resemble the native corneal epithelium and (2) have adequate
modulation in keratin expressions toward a corneal character [23].
Clinical trials using autologous epithelial cell sheets have showed
the sheets' efficacy for reconstructing the ocular surface in patients
with corneal limbal stem cell deficiencies [22, 24].
