MECHANO-ACTIVE SCAFFOLDS - Intelligent Scaffolds for Tissue Engineering and Regenerative Medicine - page 554

Figure 27.9. Histological studies of the cell-scaffold constructs explanted
fromnudemiceat8weeks(tissuesections).Thesectionswerestainedwith
H&E (a, e), Masson's trichrome (b ,f), Alcian blue (b, g), or safranin O (d, h).
The images represent the PLCL-chondrocyte constructs (a-d) and the PLA-
chondrocyte constructs (e-h). (The full color images can be found in the
online version of thisarticle.) See also Color Insert.
accumulationofECMonthecell-PLCLconstructsdemonstratesthat
these scaffolds can not only sustain but significantly enhance chon-
drogenic differentiation. Moreover, the mechanical stimulation of
the dynamic in vivo environment promotes deposition of the chon-
dral ECM onto implanted PLCL scaffolds (Fig. 27.9). In contrast, on
the PLA scaffolds, most of the chondrocytes de-differentiate and
form fibrous tissues. In the rabbit defect model, animals implanted
with PLCL scaffolds exhibit significantly enhanced cartilage regen-
eration compared with those that receive an empty control or PLGA
scaffold. These results indicated that the mechano-active PLCL scaf-
folds effectively deliver mechanical signals associated with biolog-
ical environments to adherent chondrocytes, suggesting that these
elasticPLCLscaffoldscansuccessfullybeusedforcartilageregener-
ation.
Consequently, in mechano-active cartilage regeneration, it is
important that the implants that are inserted to the defect sites not
onlymaintaintheirmechanicalintegritybutalsodelivermechanical
signals to adherent cells in the body. In order to effectively trans-
fer these mechanical signals, the scaffold material must completely
recoverfromdeformationsinducedbyvariousbodyforces.Withthis