Abstract
Hydrogels are promising materials for cartilage
repair, but the properties required for optimal functional outcomes
are not yet known. In this study, we functionalized
four materials that are commonly used in cartilage tissue
engineering and evaluated them using in vitro cultures. Gelatin,
hyaluronic acid, polyethylene glycol, and alginate were
functionalized with methacrylic anhydride to make them photocrosslinkable.
We found that the responses of encapsulated
human chondrocytes were highly dependent on hydrogel
type. Gelatin hydrogels supported cell proliferation and the
deposition of a glycosaminoglycan rich matrix with significant
mechanical functionality. However, cells had a dedifferentiated
phenotype, with high expression of collagen type I.
Chondrocytes showed the best redifferentiation in hyaluronic
acid hydrogels, but the newly formed matrix was highly
localized to the pericellular regions, and these gels degraded
rapidly. Polyethylene glycol hydrogels, as a bioinert control,
did not promote any strong responses. Alginate hydrogels
did not support the deposition of new matrix, and the stiffness
decreased during culture. The markedly different
response of chondrocytes to these four photocrosslinkable
hydrogels demonstrates the importance of material properties
for chondrogenesis and extracellular matrix production,
which are critical for effective cartilage repair.
repair, but the properties required for optimal functional outcomes
are not yet known. In this study, we functionalized
four materials that are commonly used in cartilage tissue
engineering and evaluated them using in vitro cultures. Gelatin,
hyaluronic acid, polyethylene glycol, and alginate were
functionalized with methacrylic anhydride to make them photocrosslinkable.
We found that the responses of encapsulated
human chondrocytes were highly dependent on hydrogel
type. Gelatin hydrogels supported cell proliferation and the
deposition of a glycosaminoglycan rich matrix with significant
mechanical functionality. However, cells had a dedifferentiated
phenotype, with high expression of collagen type I.
Chondrocytes showed the best redifferentiation in hyaluronic
acid hydrogels, but the newly formed matrix was highly
localized to the pericellular regions, and these gels degraded
rapidly. Polyethylene glycol hydrogels, as a bioinert control,
did not promote any strong responses. Alginate hydrogels
did not support the deposition of new matrix, and the stiffness
decreased during culture. The markedly different
response of chondrocytes to these four photocrosslinkable
hydrogels demonstrates the importance of material properties
for chondrogenesis and extracellular matrix production,
which are critical for effective cartilage repair.
| Original language | English |
|---|---|
| Pages (from-to) | 2544-2553 |
| Number of pages | 10 |
| Journal | Journal of Biomedical Materials Research. Part A. |
| Volume | 102 |
| Issue number | 8 |
| DOIs | |
| Publication status | Published - 2014 |
Keywords
- cartilage
- hydrogels
- photopolymerization
- chondrogenesis
- tissue engineering