title: Porous chitosan scaffold containing microspheres loaded with transforming growth factor-beta1: implications for cartilage tissue engineering.
abstract: Damaged articular cartilage, caused by traumatic injury or degenerative diseases, has a limited regenerative capacity and frequently leads to the onset of osteoarthritis. As a promising strategy for the successful regeneration of long-lasting hyaline cartilage, tissue engineering has received increasing recognition. In this study, we attempted to design a novel type of porous chitosan scaffold, containing transforming growth factor-beta1 (TGF-beta1), to enhance chondrogenesis. First, to achieve a sustained release of TGF-beta1, chitosan microspheres loaded with TGF-beta1 (MS-TGFs) were prepared by the emulsion method, in the presence of tripolyphosphate; with an identical manner, microspheres loaded with BSA, a model protein, were also prepared. Both microspheres containing TGF-beta1 and BSA had spherical shapes with a size ranging from 0.2 to 1.5 microm. From the release experiments, it was found that both proteins were slowly released from the microspheres over 5 days in a PBS solution (pH 7.4), in which the release rate of TGF-beta1 was much lower than that of BSA. Second, MS-TGFs were seeded onto the porous chitosan scaffold, prepared by the freeze-drying method, to observe the effect on the proliferation and differentiation of chondrocytes. It was obviously demonstrated from in vitro tests that, compared to the scaffold without MS-TGF, the scaffold containing MS-TGF significantly augments the cell proliferation and production of extracellular matrix, indicating the role of TGF-beta1 released from the microspheres. These results suggest that the chitosan scaffold containing MS-TGF possesses a promising potential as an implant to treat cartilage defects.
authors.affiliation: Biomedical Research Center, Korea Institute of Science and Technology, 39-1 Haweolgog-dong, Sungbook-gu, Seoul 136-791, South Korea.
authors.forename: Sung Eun
authors.initials: SE
authors.lastname: Kim
authors.forename: Jae Hyung
authors.initials: JH
authors.lastname: Park
authors.forename: Yong Woo
authors.initials: YW
authors.lastname: Cho
authors.forename: Hesson
authors.initials: H
authors.lastname: Chung
authors.forename: Seo Young
authors.initials: SY
authors.lastname: Jeong
authors.forename: Eunhee Bae
authors.initials: EB
authors.lastname: Lee
authors.forename: Ick Chan
authors.initials: IC
authors.lastname: Kwon
mesh_terms: D000818:Animals; D002356:Cartilage / Q000187:drug effects / Q000648:ultrastructure*; D002417:Cattle; D002686:Chitin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D048271:Chitosan; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000493:pharmacokinetics; D008863:Microspheres; D016062:Porosity; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D016212:Transforming Growth Factor beta / Q000008:administration & dosage / Q000493:pharmacokinetics*; D053773:Transforming Growth Factor beta1
chemical_list: D003692:Delayed-Action Preparations; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D002686:Chitin; D048271:Chitosan