Biomimetic ECM Scaffolds Prepared from Cultured Cells - Biomimetics: Advancing Nanobiomaterials and Tissue Engineering - page 245

All of the results from the host tissue response analyses indicate excel-
lent biocompatibility of the aECM scaffolds, which is essential for ideal
tissue engineering scaffolds. Furthermore, the use of autologous serum
and serum-free culture is technically possible to reduce the use of animal
serum and to minimize the potential side effects induced by exogenous
materials [37, 38].

10.4 Application of Cultured Cell-Derived ECM

Scaffolds

The ECM scaffolds prepared from cultured cells have been used for tis-
sue engineering of cartilage and dermis [29]. ECM-M and ECM-C were
used for the culture of MSCs in chondrogenic induction medium to inves-
tigate their effects on cartilage tissue regeneration. MSC are seeded in
both ECM-M and ECM-C. The cell seeding effi ciency in the ECM-M and
ECM-C is 82.1 ± 4.5% and 81.0 ± 6.5%, respectively. Observation with an
optical microscope and a SEM demonstrate that MSCs attach well to the
fi bers and fl akes of the ECM-M and ECM-C scaffolds. However, there is
no obvious difference between the ECM-M and ECM-C scaffolds in the
cell seeding effi ciency, cell distribution and morphology.
The gross appearances of the engineered cartilage after culture for 1, 2
and 4 weeks in the ECM scaffolds are glisteningly white, which is similar
to native cartilage. The tissues become larger during the culture in ECM
scaffolds. The size of tissues formed in the ECM scaffolds is larger than
that of the pellet-cultured MSCs. After 1 week of culture, the MSCs pro-
liferate and secrete new ECM to occupy the spaces in the ECM scaffolds.
The cell viability after culture in the scaffolds for 4 weeks is examined by
live-dead staining. Green living cells are observed and very few red dead
cells are detected. These results indicate that the cells show high viability
when being cultured in the ECM scaffolds. The sGAG content and dry
weight of the engineered tissues using the ECM scaffolds are higher than
those of the tissues constructed by conventional pellet culture. The sGAG
content and dry weight increase with the culture time. There is no obvious
difference between ECM-M and ECM-C. These results indicate that the
ECM scaffolds promote the secretion of ECM.
The chondrogenic differentiation of MSCs is investigated by histologi-
cal, immunohistochemical and real-time PCR analyses. Toluidine blue
staining indicates the typical cartilaginous metachromasia of the engi-
neered tissues. The tissues formed in the ECM scaffolds are more strongly
stained than those formed by pellet culture. The cells exhibit a polygonal
shape and are surrounded by cartilaginous ECM in ECM-M and ECM-C.
Immunohistological staining with antibodies against type II collagen and
aggrecan reveals the cartilage-specifi c ECM composition of the engineered