HYBRID POROUS SCAFFOLDS OF BIODEGRADABLE SYNTHETIC POLYMERS AND COLLAGEN FOR TISSUE ENGINEERING - Intelligent Scaffolds for Tissue Engineering and Regenerative Medicine - page 424

The PLGA-collagen hybrid mesh has been used for culturing fibrob-
lasts,tenocytes,chondrocytes,andosteoblasts.Theweblikecollagen
microspongesinthePLGA-collagenfacilitatedcelladhesionanddis-
tribution in the hybridmesh.
The PLGA-collagen hybrid mesh has also been used for the tis-
sue engineering of cartilage. 15 Chondrocytes isolated from bovine
articularcartilagewereseededinthehybridmeshbydroppingacell
suspensioninaculturemediumontothehybridmesh.Thechondro-
cytesadheredtotheweblikehybridmeshandshowedauniformdis-
tribution on the mesh. The cells continued to proliferate and regen-
erated a cartilaginous matrix, filling the voids in the hybrid mesh.
The weblike collagen microsponges that formed in the openings of
the knitted mesh not only prevented the seeded cells from passing
throughthehybridmeshbutalsoincreasedthespecificsurfacearea
to provide su cient surface for a spatially even cell distribution.
After being cultured in vitro for one day, the cell/mesh sheets were
used in single-sheet form to regenerate thin cartilage implants or in
laminatedformtoyieldthickcartilageimplants.Thethicknessofthe
implant could be manipulated by varying the number of laminated
mesh sheets. The cell/mesh sheets could also be rolled up in the
shape of a cylinder, in which case the thickness of the implant was
adjusted by the height and the diameter of the roll by the number
of sheets used. As cells were seeded within each sheet of the hybrid
mesh, the density and distribution of the seeded cells in the over-
all laminated or rolled form were as high and uniform as those in
the single-sheet form. A round, disk-shaped single sheet, five-sheet,
and 8 mm high roll implants after 4, 8, and 12 weeks' implantation
retained their original shapes and appeared pearly white. The good
mechanicalpropertiesofthehybridmeshandspatialhomogeneous
celldistributionhelpthetissue-engineeredcartilageimplantsretain
the same shapes as the original scaffolds. In the cases of the lami-
nated and rolled implants, the implanted sheets became integrated
with each other. Histological examination showed that the chondro-
cytes had a round morphology. Alcian blue staining indicated that
glycosaminoglycans(GAGs)wereabundantandhomogeneouslydis-
tributedthroughouttheimplants(Fig.22.5).Toluidinebluestaining
demonstratedthetypicalmetachromasiaofarticularcartilage.Type
II collagen was detected by immunohistological staining. Northern