Biomedical Engineering Reference
In-Depth Information
b)
a)
c)
d)
kDa
150
8000
*
*
7000
6000
5000
4000
3000
2000
1000
0
100
75
*
50
35
Figure 13.2
Histological fi ndings of
pharyngeal cells and results of zymography of
MMP-2 of pharyngeal cells grown on a
polymer surface. (a) Phase-contrast micros-
copy of pharyngeal cells grown on polystyrene
surface of commercially available cell culture
dishes is shown. Pharyngeal cells showed a
confl uent monolayer on the surface of 35-mm
cell cultures dishes after 3 days with the
typical cuboid morphology of epithelial cells.
Smooth muscle cells of the pharyngeal
epithelium are labeled by white arrows
(magnifi cation
×
20). (b) In order to better
visualize the pharyngeal cells after cell
seeding on the polymer surface, Coomassie
Blue staining was used. Pharyngeal cells
began to form colonies after cell seeding and
started to become confl uent on Day 3 of cell
growth (magnifi cation
×
20). (c) SDS - substrate
gel electrophoresis (zymography) of primary
cell cultures of the pharynx grown on the
polymer surface is shown. The kinetics of
appearance and activity levels of 72 kDa
(MMP-2) band of pharyngeal cells are shown
on Day 1, 3, 9, and 12 of cell growth. Bands
are marked by arrows. The gelatinolytic
activities of media conditioned by pharyngeal
cells grown on the polymer surface were
normalized to equal cell numbers. (d)
Scanning densitometry units of the gelantino-
lytic bands are shown. Statistical analysis was
performed to determine differences of MMP-2
levels between Day 1 and the subsequent
days of cell growth. Statistically signifi cant
differences (
P
≤
0.05) are marked by a star.
Data taken from three independent experi-
ments (values are mean
±
SD). Parts c and d
reprinted from [111], Copyright 2007, with
permission from IOS Press.
edge is based on cell culture investigations and it is unknown if these mechanisms
are also found
in vivo
[124, 125] . A fundamental requirement for a successful
application of degradable implant materials for the pharyngeal reconstruction
in vivo
is a saliva-tight integration of the material in surrounding tissues to avoid
salivary fi stulae with destruction of neighboring soft tissue. The development of
long-term degradable polymeric scaffolds for pharyngeal reconstruction has to
guarantee an adequate biocompatibility and biofunctionality as well as growth
of a functional tissue formation considering the specifi c physiological and
