Effects of a chitosan scaffold containing TGF-beta1 encapsulated chitosan microspheres on in vitro chondrocyte culture.
The objectives of this study were (1) to develop a three-dimensional chitosan scaffold in combination with transforming growth factor-beta1 (TGF-beta1)-loaded chitosan microspheres and (2) to evaluate the effect of the TGF-beta1 release on the chondrogenic potential of rabbit chondrocytes in the scaffolds. TGF-beta1 was loaded into chitosan microspheres using an emulsion-crosslinking method, resulting in spherical shapes with a size ranging from 0.3 to 1.5 microm. Controlled release of TGF-beta1, as measured by enzyme-linked immunosorbent assay (ELISA), was observed with chitosan microspheres over 7 days. Chitosan solutions (2% and 3%) were fabricated into two types of scaffolds with different pore morphologies and mechanical properties using a freeze-drying technique, with the result that scaffold with higher concentrations showed smaller pores and lower porosity, leading to a much stronger scaffold. The TGF-beta1 microspheres were incorporated into the scaffolds at a concentration of 10 ng TGF-beta1/scaffold and then chondrocytes seeded into each scaffold and incubated in vitro for 2 weeks. The 2% chitosan scaffolds showed higher cell attachment levels than the 3% chitosan scaffolds (P < 0.01), regardless of the TGF-beta1 microspheres. Both the proliferation rate and glycosaminoglycan (GAG) production were significantly higher for scaffolds incorporating TGF-beta1 microspheres than for the control scaffolds without microspheres 10 days after incubation. Extracellular matrix staining by Safranin O and immunohistochemistry for type II collagen both significantly increased in scaffolds containing TGF-beta1 microspheres. These results suggest that the TGF-beta1 microsphere incorporated in scaffolds have the potential to enhance cartilage formation.
Department of Orthopedic Surgery, Seoul National University College of Medicine, Seoul, Korea.
Jong Eun
JE
Lee
Seoung Eun
SE
Kim
Ick Chan
IC
Kwon
Hyun Jeong
HJ
Ahn
Hyunchul
H
Cho
Sang-Hoon
SH
Lee
Hee Joong
HJ
Kim
Sang Cheol
SC
Seong
Myung Chul
MC
Lee
D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage / Q000378:metabolism; D002356:Cartilage / Q000187:drug effects; D018929:Cell Culture Techniques; D048271:Chitosan / Q000008:administration & dosage* / Q000378:metabolism*; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D008863:Microspheres; D011817:Rabbits; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods; D016212:Transforming Growth Factor beta / Q000008:administration & dosage* / Q000378:metabolism*; D053773:Transforming Growth Factor beta1
D001672:Biocompatible Materials; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D048271:Chitosan