Biomedical Engineering Reference
In-Depth Information
able to integrate with soft tissues, mechanically dense tissues such as cartilage
and bone present significant challenges for creating strong tissue-biomaterial
interactions. Cartilage poses a particularly difficult challenge for biomate-
rial integration since it lacks the ability to self repair, and possesses a dense
extracellular matrix that impedes cellular migration and tissue integration.
Integration of cartilage tissue has been the focus of numerous recent investi-
gations with many studies examining the integration of both the engineered
and native cartilage with host tissue.
Jurgensen et al. investigated the efficacy of tissue transglutaminase as
a biological glue for integrating two cartilage pieces together [320]. In our lab-
Fig. 10
Schematic illustration for the strategy of hydrogel-cartilage integration by tissue-
initiated photopolymerization. Individual steps of the process are (1) clearance of the
proteoglycans in cartilage by chondroitinase to expose the collagen network; (2) in situ
generation of tyrosyl radicals by photo-oxidation of tyrosine residues on collagen with
H
2
O
2
under low intensity UV irradiation; and (3) introduction of a macromer solution
and in situ photo-gelation via tyrosyl radical initiation and UV-excitation (Reprinted with
permission Advanced Functional Materials [321])
