PGA FIBER FOR SOFT TISSUE ENGINEERING - Intelligent Scaffolds for Tissue Engineering and Regenerative Medicine - page 704

at 37 ◦ C in the incubator for eight weeks with medium change twice
a week. The cell-PGA constructs cultured without pulsatile radial
stress were setup asa control.
After eight weeks, the SMC-PGA constructs were transformed
into a tubular structure with excellent elasticity and a round lumen
6 mm in diameter when cultured under dynamic mechanical load-
ing.Incontrast,vesselwallsderivedfromthestaticgrouprevealeda
collapsed lumen structure and a rough surface when pulsatile stim-
ulation was notapplied (Fig. 34.19).
Histology revealed the structure with multiple layers of SMCs
and orientated orderly in the vessel walls of the dynamic group
with collagenous fibers distributed evenly in the vessel wall and
complete degradation of PGA fibers. On the contrary, randomly
orientatedSMCstogetherwithdisorganizedcollagenousfiberswere
observed in the staticgroup (Fig. 34.20).
The above findings were further confirmed by the results of
immunohistochemical staining for SM α -actin and calponin in the
dynamic group. In contrast, fewer cells positive for SM α -actin
and calponin with a disorganized pattern were observed in the
Figure 34.19. Grossviewofengineeredvessels.Vesselwallswitharound
lumen (6 mm in diameter) are formed after 4 (a) and 8 (c) weeks of culture
with pulsatile stimulation. Vessel walls with a collapsed lumen and a rough
surfaceareobservedafter4(b)and8(d)weeksofculturewithoutpulsatile
stimulation. (Reprinted by permission from Ref. 20).