Assessment of fixed charge density in regenerated cartilage by Gd-DTPA-enhanced MRI.
OBJECTIVE
Applying regenerated cartilage in a clinical setting requires noninvasive evaluation to detect the maturity of cartilage tissue. Magnetic resonance (MR) imaging of articular cartilage is well accepted and has been applied clinically in recent years. We attempt to establish a noninvasive method to evaluate the maturity of regenerated cartilage tissue using gadolinium-enhanced MR imaging.


METHODS
To reconstruct cartilaginous tissue, we embedded articular chondrocytes harvested from bovine humeral head in agarose gel and cultured the cells in vitro up to 4 weeks. The fixed charge density (FCD) of the cartilage was determined using MRI gadolinium exclusion method. The sulfated glycosaminoglycan (sGAG) content was determined by dimethylmethylene blue dye-binding assay.


RESULTS
The sGAG content and FCD of the regenerated cartilage increased with duration of culture. In the T1Gd maps, the [Gd-DTPA(2-)] in the specimen decreased, and the boundary between the sample disk and the bath solution of phosphate buffered saline (PBS) became clearer as time in culture increased. In the linear regression analysis, FCD and sGAG content correlated significantly.


CONCLUSIONS
Gadolinium-enhanced MR imaging measurements can be useful predictors of the degree of cartilaginous tissue formation.
Miyata
Shogo
S
Graduate School of Life Science and System Engineering, Kyushu Institute of Technology, Japan. miyata@life.kyutech.ac.jp
Homma
Kazuhiro
K
Numano
Tomokazu
T
Furukawa
Katsuko
K
Tateishi
Tetsuya
T
Ushida
Takashi
T
D000818:Animals; D015519:Bone Density / Q000502:physiology*; D001857:Bone Matrix / Q000166:cytology / Q000502:physiology; D001861:Bone Regeneration / Q000502:physiology*; D002358:Cartilage, Articular / Q000166:cytology / Q000502:physiology*; D002417:Cattle; D019902:Chondrocytes / Q000502:physiology; D004396:Coloring Agents; D003287:Contrast Media / Q000008:administration & dosage*; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D006025:Glycosaminoglycans / Q000378:metabolism; D006811:Humerus / Q000166:cytology / Q000502:physiology; D007089:Image Enhancement; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008751:Methylene Blue / Q000031:analogs & derivatives; D023421:Models, Animal
D004396:Coloring Agents; D003287:Contrast Media; D006025:Glycosaminoglycans; C435946:dimethylmethylene blue; C013786:A73025; D019786:Gadolinium DTPA; D008751:Methylene Blue