PURPOSE: The purpose of this study was to investigate the effects of transplantation of an in vitro-generated, scaffold-free, tissue-engineered cartilage tissue analogue (CTA) using a suspension chondrocyte culture in a rabbit growth-arrest model. MATERIALS AND METHODS: We harvested cartilage cells from the articular cartilage of the joints of white rabbits and made a CTA using a suspension culture of 2x107 cells/mL. An animal growth plate defect model was made on the medial side of the proximal tibial growth plate of both tibias of 6-week-old New Zealand white rabbits (n=10). The allogenic CTA was then transplanted onto the right proximal tibial defect. As a control, no implantation was performed on the left-side defect. Plain radiographs and the medial proximal tibial angle were obtained at 1-week intervals for evaluation of bone bridge formation and the degree of angular deformity until postoperative week 6. We performed a histological evaluation using hematoxylin-eosin and Alcian blue staining at postoperative weeks 4 and 6. RESULTS: Radiologic study revealed a median medial proximal tibial angle of 59.0degrees in the control group and 80.0degrees in the CTA group at 6 weeks. In the control group, statistically significant angular deformities were seen 3 weeks after transplantation (p<0.05). On histological examination, the transplanted CTA was maintained in the CTA group at 4 and 6 weeks postoperative. Bone bridge formation was observed in the control group. CONCLUSION: In this study, CTA transplantation minimized deformity in the rabbit growth plate injury model, probably via the attenuation of bone bridge formation.
Animals ; *Bone Transplantation ; Cartilage/anatomy & histology ; Cell Culture Techniques ; Cells, Cultured ; Chondrocytes/*cytology/transplantation ; Growth Plate/anatomy & histology/*surgery ; *Mesenchymal Stem Cell Transplantation ; Rabbits ; Tibia/*surgery ; Tissue Engineering ; Transplantation, Autologous/methods ; Transplantation, Homologous

Articular cartilage damage is very common in clinical practices. Due to the low self healing abilities of articular cartilage, it must be repaired or substituted by implants once natural articular cartilage is damaged. On the other hand, the various technologies currently used for healing damaged articular cartilage are little satisfactory, and rarely restore full function or return the tissue to its natively normal state. Tissue engineering technology holds great promise for the healing of damage or defects of articular cartilage. Tissue engineered articular cartilage is one of the most promising methods for repairing articular cartilage trauma and defects. In this paper, the authors review the research progress of three elements such as seed cells, growth factors and scaffolds which constitute tissue engineered articular cartilage.
Animals ; Cartilage, Articular ; injuries ; surgery ; Chondrocytes ; transplantation ; Humans ; Mesenchymal Stem Cell Transplantation ; methods ; Osteoblasts ; cytology ; Tissue Engineering ; methods ; Tissue Scaffolds

BACKGROUNDMatrix-induced autologous chondrocyte implantation (MACI) is the third generation tissue-engineering technique for the treatment of full-thickness articular cartilage defects. The aim of this study was to describe this new technique and the postoperative findings in adolescent knee with focal chondral defect.

METHODSThe MACI consists of diagnostic arthroscopy and cartilage harvest, chondrocyte culture and seeding in tissue-engineering collagenous membrane, and implantation of the scaffold. Clinical outcome at minimum 1-year follow-up was assessed in seven patients (mean age (16.6 ± 1.5) years; 14 - 19 years) with full-thickness cartilage defects, with International Knee Documentation Committee (IKDC) score, the International Cartilage Repair Society (ICRS) score and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Besides, MR imaging was performed with T1 and T2-weighted imaging and three-dimensional spoiled gradient-recalled (3D-SPGR) MR imaging.

RESULTSClinical evaluation showed significant improvement and MRI analysis showed that the structure was homogeneous and the implant surface was regular and intact in six patients, but irregular in one. Of all the seven patients, the cartilage defect site was nearly totally covered by the implanted scaffold.

CONCLUSIONSThese results indicated that MACI technique is an option for cartilage defect in adolescent knee joint, especially large defect of over 2 cm(2). Long-term assessment is necessary to determine the true value of this technique.

Adolescent ; Adult ; Cartilage, Articular ; injuries ; surgery ; Cells, Cultured ; Chondrocytes ; cytology ; physiology ; Female ; Humans ; Knee Joint ; cytology ; surgery ; Male ; Tissue Engineering ; methods ; Transplantation, Autologous ; methods ; Young Adult

OBJECTIVE: To observe the effect of daily low-intensity pulsed ultrasound (LIPUs) therapy on improving the enchondral bone formation in lumbar fusion in rabbit models, and to explore its possible mechanism. METHODS: Posterolateral noninstrumented bilateral fusions were performed at the L5 approximately L6 levels in 20 New Zealand rabbits. The autograft iliac bone was implanted on the left side, and the hydroxyapatite bioceramic artificial bone on the right. The rabbits were divided into a treatment group and a control group randomly. One week after the surgery, LIUPs was administered for 20 minutes per day for 4 weeks over the fusion site in the treatment group and false treatment was used in the control group. Post-anterior X-ray photographs were taken to determine the conditions of fusion area, and then, rabbits were killed and the fusion tissues were obtained. Chondrocytes were detected by histological and cytological methods. RESULTS: Compared with the control group, the fusion rate of the treatment group was significantly up-regulated (P<0.05). There was plenty bone trabecula in the fusion area in the treatment group, the number of chondrocytes was also higher than that of the control group (P<0.05), and there was no statistical difference in the number of chondrocytes between the iliac and artificial bone tissues after the treatment(P>0.05). CONCLUSION Low-intensity pulsed ultrasound therapy improves the endochondral bone formation in the lumbar spine fusion in rabbit models.
Animals ; Chondrocytes ; cytology ; Durapatite ; therapeutic use ; Female ; Ilium ; transplantation ; Lumbar Vertebrae ; surgery ; Male ; Osteogenesis ; radiation effects ; Rabbits ; Random Allocation ; Spinal Fusion ; methods ; Ultrasonic Therapy ; methods

OBJECTIVETo test the hypothesis that tissue-engineered cartilage can be bioincorporated with a nonreactive, permanent endoskeletal scaffold.

METHODSChondrocytes obtained from swine articular were seeded onto polyglycolic acids(PGA) scaffold which was incorporated with high-density polyethylene (Medpor). After cultured in vitro for two weeks,the cell-scaffold construct was implanted into subcutaneous pockets on the back of nude mice. Six weeks later,the newly formed cartilage prosthesis was harvested, and a small part of sample was evaluated by gross view, histology, type II collagen immunohistochemistry and biochemistry. PGA scaffold seeded with cells as the control group.

RESULTSThe newly formed cartilage was very similar to normal cartilage in both gross view and histology, and jointed Medpor tightly. The center of control group was hollow.

CONCLUSIONThis pilot technique combining tissue engineering with a permanent success in creating cartilage without "hollow" phenomenon. biocompatible endoskeleton demonstrated

Animals ; Biocompatible Materials ; Cartilage ; transplantation ; Chondrocytes ; cytology ; Materials Testing ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Pilot Projects ; Polyethylenes ; Swine ; Tissue Engineering ; methods ; Tissue Scaffolds

OBJECTIVESTo induce autologous bone marrow derived mesenchymal stem cell (aMSC) into chondrocyte, and to confirm the effects of 3 dimensional (3D) dynamic inducing in vitro and their long-term animal model repairing in vivo.

METHODSaMSC were separated from rabbits bone marrow aspirates, then respectively experienced 3D dynamic inducing in alginate drops in modified rotating wall bioreactor culture or in two dimensional (2D) inducing (culture flask) for 10 d. The induced cells were harvest and then mixed with fibrin sealant (FS) to repair rabbit knee femoral trochlea cartilage defects model. After 8, 12, 24, 48 weeks animals were euthanized. Gross appearance, histological appearances were examined.

RESULTSFlask culture groups showed a little chondrocyte differentiation, 3D inducing group showed obviously chondrocyte differentiation, improved collagen II and proteoglycan production. For 3D inducing ones in vivo, the cartilage defects were smoothly repaired by white translucent hard tissue with obvious hyaline-like cartilage histological appearance after 8, 12 weeks, and the defects boundary were hard to be identified with hyaline like cartilage with sustained histological appearance and score after 24, 48 weeks. For 2D ones in vivo, the cartilage defects were smoothly repaired after 8 weeks by hyaline like cartilage which showed accelerated degeneration after 24 weeks and lose cartilage performance completely after 48 weeks.

CONCLUSIONS3D dynamic inducing may assist aMSC on differentiating into chondrocyte, improve its long-term in vivo repairing effects, and enlighten its further applications in tissue engineering cartilage.

Animals ; Bone Marrow Cells ; cytology ; Cartilage, Articular ; injuries ; physiopathology ; surgery ; Cell Culture Techniques ; Cell Differentiation ; Cells, Cultured ; Chondrocytes ; cytology ; Chondrogenesis ; Disease Models, Animal ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; cytology ; Rabbits ; Tissue Engineering ; methods ; Transplantation, Autologous ; Wound Healing

OBJECTIVETo investigate the effect of the basic fibroblast growth factor (b-FGF) to regenerate an autologous tissue-engineered cartilage in vitro.

METHODSThe Cells were harvested from the elastic auricular cartilage of swine,and were plated at the concentration of 1 x 10(4) cells/cm2 , studied in vitro at two different media enviroments: Group I contained Ham's F-12 with supplements and b-FGF, Group II contained Ham's F-12 only with supplements. The passage 2 cells (after 12.75 +/- 1.26 days) were harvested and mixed with 30% pluronic F-127/Ham's F-12 at the concentration of 50 x 10(6) cells/ml. It was injected subcutaneously at 0.5 ml per implant. The implants were harvested 8 weeks after the vivo culture and examined with the histological stains.

RESULTSThe chondrocytes displayed morphologically similar to the fibroblasts in the media containing basic-FGF. The number of cell doublings (after 12.75 +/- 1.26 days) in vitro culture was as the following: Group I, 70; Group II, 5.4. Eight 8 weeks after the vivo autologous implantation, the average weight (g) and volume (cm3) in each group was as the following: Group I, 0.371 g/0.370 cm3 Group II, 0.179 g/0.173 cm3 (P < 0.01). With the b-FGF in vitro culture, the cells were expanded by 70 times after 2 weeks. Histologically, all of the engineered cartilage in the two groups were similar to the native elastic cartilage.

CONCLUSIONThese results indicate that the basic-FGF could be used positively to enhance the quality and quantity of the seeding cells for the generation of the well-engineered cartilage.

Animals ; Cartilage ; cytology ; drug effects ; physiology ; Cell Division ; drug effects ; Cells, Cultured ; Chondrocytes ; cytology ; drug effects ; Female ; Fibroblast Growth Factors ; pharmacology ; physiology ; Male ; Regeneration ; drug effects ; Swine ; Tissue Engineering ; methods ; Transplantation, Autologous

Cartilage, Articular ; cytology ; injuries ; Cells, Cultured ; Chondrocytes ; transplantation ; Humans ; Transplantation, Autologous ; Wound Healing

OBJECTIVETo isolate and chondro-inductive culture of human adipose tissue-derived stromal cells and to study their heterotopic chondrogenesis by loading them on alginate gel.

METHODSLiposuction human adipose tissues were minced and digested with collagenase type I. The obtained stromal cells were primarily cultured in BGJb medium for ten days. Secondary harvested cells were cultured in DMEM-F12 medium supplemented with 10%FBS, 6.25 mg/L insulin, 10 mg/L TGF-beta1, 50 mg/L of freshly prepared L-ascorbate for 14 days. After in vitro assay of chondrogenic phenotypes, the cells at density of 10(10)/L were mixed with 1.2% alginate sodium and 102 mmol/L CaCl(2). The cross-linking cell-alginate gel were injected into four BALB/C athymic mice subcutaneously (1 ml for each mouse). Meanwhile, the auto-controls were set by injecting equal dose of simple alginate gel and pure cells in two opposite buttocks of the same mouse subcutaneously. Two mice were sacrificed at fourth and eighth week postoperatively and all samples were removed, fixed, embedded in paraffin and cut into sections of 5 micro m thick. HE staining, Alcian blue and modified Masson's trichrome staining were employed to observe chondrogenesis histologically.

RESULTSAlcian blue and immunocytochemical staining revealed chondroitin sulfate and collagen II in cell matrix after having been chondro-inductive cultured for 14 days. At intervals of fourth and eighth week, heterotopic chondrogenesis is (cartilage formed) within cell-alginate injected sites were found in all mice but negatively in auto-controls. Histologically the hypertrophic chondrocytes were among cartilage matrix in different staining. All alginate gel and solitory cells absorbed within two to three weeks postoperatively in auto-controls.

CONCLUSIONIt seems that stromal cells derived from human adipose tissue presents a potential for chondrogenic differentiation.

Adipose Tissue ; cytology ; Alginates ; pharmacology ; Animals ; Cell Differentiation ; Cells, Cultured ; Chondrocytes ; cytology ; metabolism ; Chondrogenesis ; Female ; Humans ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Stem Cell Transplantation ; Stromal Cells ; cytology ; metabolism ; transplantation ; Tissue Engineering

The regulation roles of insulin-like growth factor-1 (IGF-1) with basic fibroblast growth factor (bFGF) and transforming growth factor beta 2 (TGFbeta2) in human nasal septum chondrocytes monolayer culture and cartilage engineering was investigated in this study. The role of IGF-1 with bFGF and TGFbeta2 was investigated by measuring chondrocyte growth kinetic and collagen genes expression. IGF-1 together with bFGF and TGFbeta2 promote cartilage tissue engineering, increase type II collagen expression and enhance the histological features of engineered cartilage.
Cartilage/*transplantation ; Cell Division/physiology ; Chondrocytes/*cytology ; Collagen Type II/genetics ; Culture Media, Serum-Free ; Gene Expression/physiology ; Growth Substances/*physiology ; Insulin-Like Growth Factor I/*physiology ; Tissue Engineering/*methods