Self-assembly tissue engineering fibrocartilage model of goat temporomandibular joint disc / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To construct self-assembly fibrocartilage model of goat temporomandibular joint disc and observe the biological characteristics of the self-assembled fibrocartilage constructs, further to provide a basis for tissue engineering of the temporomandibular joint disc and other fibrocartilage.</p><p><b>METHODS</b>Cells from temporomandibular joint discs of goats were harvested and cultured. 5.5 x 10(6) cells were seeded in each agarose well with diameter 5 mm x depth 10 mm, daily replace of medium, cultured for 2 weeks.</p><p><b>RESULTS</b>One day after seeding, goat temporomandibular joint disc cells in agarose wells were gathered and began to self-assemble into a disc-shaped base, then gradually turned into a round shape. When cultured for 2 weeks, hematoxylin-eosin staining was conducted and observed that cells were round and wrapped around by the matrix. Positive Safranin-O/fast green staining for glycosaminoglycans was observed throughout the entire constructs, and picro-sirius red staining was examined and distribution of numerous type I collagen was found. Immunohistochemistry staining demonstrated brown yellow particles in cytoplasm and around extracellular matrix, which showed self-assembly construct can produce type I collagen as native temporomandibular joint disc tissue.</p><p><b>CONCLUSION</b>Production of extracellular matrix in self-assembly construct as native temporomandibular joint disc tissue indicates that the use of agarose wells to construct engineered temporomandibular joint disc will be possible and practicable.</p>

Effect of transforming growth factor β(1) and insulin-like growth factor-I on extracelluar matrix synthesis of self-assembled constructs of goat temporomandibular joint disc / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To examine the effects of high and low concentrations of transforming growth factor (TGF) β(1) and insulin-like growth factor-I (IGF-I) on the extracelluar matrix synthesis of the self-assembled constructs of temporomandibular joint (TMJ) disc.</p><p><b>METHODS</b>The experimental groups of self-assembled constructs were exposed to IGF-I (10, 100 µg/L) and TGF-β(1) (5, 50 µg/L), the control groups were not added with any growth factors. All groups were examined at 3 and 6 weeks for gross morphological, histological, and biochemical changes. Safranin-O/fast green staining was used to examine glycosaminoglycan (GAG) distribution, picrosirius red and immunohistochemical staining to observe type I collagen distribution. Type I collagen contents were tested by ELISA assay kit, GAG contents were measured by Blyscan GAG assay kit, and the cell numbers were quantified with a Picogreen reagent kit.</p><p><b>RESULTS</b>The growth factor groups all upregulated the matrix synthesis of the self-assembled constructs compared with control groups. TGF-β(1) (5 µg/L) and IGF-I (10 µg/L) were the two most potent concentration in increasing type I collagen and GAG synthesis and cells proliferation. IGF-I group (10 µg/L) produced nearly 2 times (109.16 ± 5.12 µg) as much type I collagen as the control group (69.13 ± 5.94 µg) at 3 weeks. The matrix contents and the number of the proliferated cells in control group and all GF groups at 6 weeks were more than those at 3 weeks.</p><p><b>CONCLUSIONS</b>IGF-I (10 µg/L) is the most beneficial growth factor and can be applied in tissue-engineering stratigies of the temporomandibular joint disc. At the same time, the exposure time of growth factors is another key factor that affects matrix synthesis of TMJ disc constructs.</p>