Objective To review research progress of corneal tissueengineering.Methods The recent articles on corneal tissue engineering focus on source and selection of corneal cells, the effects of growth factors on culture of corneal cells in vitro. The preparation and selection of three-dimensional biomaterial scaffolds and their b and weak points were discussed. Results The corneal tissue engineering cells come from normal human corneal cells. The embryo corneal cell was excellent. Several kinds of growth factors play important roles in culture, growth and proliferation of corneal cell, and incroporated into matrix.Growth factors including basic fibroblast growth factor, keratinocyte growth factor, transforming growth factor β1 and epidermal growth factor was favor to corneal cell. Collagen, chitosan and glycosaninoglycans were chosen as biomaterial scaffolds. Conclusion Human tissue engineering cornea can be reconstructed and transplanted. It has good tissue compatibility and can be used as human corneal equivalents.
ObjectiveTo summarize the research progress of tissue-engineered bile duct in recent years. MethodsThe related literatures about the tissue-engineered bile duct were reviewed. ResultsIn recent years, the research of tissue-engineered bile duct has made a breakthrough in scaffold materials, seed cells, growth factors etc. However, the tissue-engineered bile duct is still in the research stage of animal experiments, which can not be directly applied to clinical practice. ConclusionsThe research of tissue-engineered bile duct becomes popular at present. With the rapid development of materials science and cell biology, the basic research and clinical application of tissue-engineered duct will be more in-depth research and extension, which might bring new ideas and therapeutic measures for patients with biliary defect or stenosis.
Objective To review the current condition of growth factors and their application to clinical treatment of acute and chronic wounds. Methods Data from the literature and Medline were analyzed according to their different uses in acute and chronic wounds. Their potential side-effects were studied. Results All data showed that wound healing time in acute and chronic wounds was accelerated and wound healing quality was improved after treatment with growth factors. No sideeffect was observed. Conclusion The efficacy and safety of growth factors in improving wound healing were confirmed. However, some reconsideration aboutpotential problems of growth factors must be made to apply them clinically in the future.
Objective To review the research progress of growth factor sustained-release microspheres in fat transplantation. Methods The recently published 1iterature at home and abroad related the growth factor sustained-release microspheres in fat transplantation was reviewed and analyzed. Results The sustained-release microsphere carrier materials include natural polymer materials and synthetic polymer materials.The sustained-release complexes of different microsphere materials with different growth factors can promote the vascularization of transplanted fat in a timely manner, improve the survival rate of grafts, and reduce the incidence of complications such as liquefaction, calcification, and necrosis. Conclusion The growth factor sustained-release microspheres have the characteristics of persistence and controllability, which is a research hotspot in the field of fat transplantation and has broad application prospects.
OBJECTIVE: To review research progress of the relation between growth factor and repair of intervertebral disc. METHODS: The recent articles on growth factor and repair of intervertebral disc were extensively reviewed. The expression of growth factor in intervertebral disc and the effect of growth factor on disc cells were investigated. RESULTS: Some growth factors play roles in the development and degeneration of intervertebral disc. Exogenous growth factor can increase proliferation of disc cells and production of proteoglycans and collagens. Gene of growth factor can be transferred to intervertebral disc cell by adenovirus. CONCLUSION: Growth factor plays an important role in the regulation of development and degeneration of interertebral disc. The above results show that the feasibility of usage of growth factor in the treatment of disc degeneration and in repair and reconstruction of disc.
Objective To review the recent progress of the researches in the field of cartilage tissue engineering, and to discuss the challenges in construction of tissue engineered cartilage. Methods Literature related with cartilage tissue engineering was reviewed and analyzed. Results Some techniques have been appl ied in cl inical. As far as the seeding cells, induced pluripotent stem cells have attracted much more attention. Current strategies of scaffold designing are trying to imitate both component and structure of natural extracellular matrix. Cartilage regeneration through the autologous cell homing technique el iminate the transplantation of exotic cells and has become the hot topic. Conclusion Successful treatment of the damaged cartilage using tissue engineering method will depend on the advances of stem cell technology development, biomimetic scaffolds fabrication and proper appl ication of growth factors.
Objective To observe the heterotopic osteogenes is of the autogenou s marrow stromal cells (MSCs) on the ceramic bovine bone(CBB)/hydrogel scaffold (HG) and t he effects of the recombinant human bone morphogenetic protein2 (rhBMP-2) and the transforming growth factor β (TGF-β) on osteogenesis. Methods The auto genous marrow stromal cells were cultured by the mineralized condition medium (1 0%FBS, dexamethasone 10 nmol, L-vitamin C 50 mg/L, βsodium glycerophosph ate D MEM culture medium 10 mmol). At 5 days, the MSCs differentiation was observed b y TypeⅠcollagen, the Mend calcium-cobalt staining, and the Von-Kossa staining. The cell suspension of 5×106/ml was obtained. There were three groups: Group A: added in rhBMP-2（10 μg）TGF-β（0.05 μg）;Group B: added in TGF-β(0.05 μg); and Group C (the control group): without the growth factor. Then, the MSCs loading on CBB/HG were embedded in the autogenous subcutaneous area at 4 and 8 weeks, and the osteogenesis was observed by the HE staining and the modified Mallory’s trichrome staining, with an image analysis. TypeⅠcollagen and the bone m orphogenetic synthesis were examined by the immunohistochemistry stains. Results Most MSCs induced by the mineralized condition medium at 5 da ys became smalle r and polygon-shaped, and the cytodendrite became shorter. The MSCs were observ e d by the Mend calciumcobalt staining. Some brown and black grains were found in the cytochylema. The MSCs were positive for the TypeⅠcollagen immunohistochemi stry stains. At 20 days, the mineralized nubs were found by the Von Kossas stain s. At 4 weeks, some strips of the new bone were observed by the HE staining an d the modified Mallory’s trichrome staining in all the groups. The bone matrix a rea was significantly larger in Group A than in Group B（P＜0.01). The av erag e gray degrees of TypeⅠcollagen were lower in Groups A and B than in Group C. However, there was no significant difference in the bone morphogenesis among the three groups. At 8 weeks, there- were significantly more snatchy strips and macula mature bone formation in Groups A and B than in Group C. The Type Ⅰcollage n and the bone morphogenesis were not significantly different among the three groups. Conclusion The autogenous marrow stromal cells on the ce ramic bovine bon e /hydrogel scaffold can promote the heterotopic osteogenesis, and the combined use of rhBMP-2 and TGF-β is better than the only use of rhBMP-2 or TGF-β i n promoting osteogenesis.
Objective To investigate the effect of acid, basic fibroblast growth factor (aFGF, bFGF) and epidermal growth factor (EGF), andtheir combination on the proliferation of rabbit anterior cruciate ligament (ACL) and medial collateral ligament (MCL) in vitro. Methods Thecells of ACL and MCL were isolated and subcultured from the knee joints of tenweek-old New Zealand white rabbits. The cells were seeded into 96-well corning cluster plates. Three growth factors of different concentration alone or in combination were added into the culture medium respectively, which were 0, 1, 5, 10, 50 and 100 ng/ml for aFGF, bFGF and 0, 1.56, 3.13, 6.25, 12.5, 25 and 50 ng/ml for EGF. The proliferation of the fibroblasts was measured for 48 h with XTT method. Results All of the three growth factors alone promoted the cell proliferation of ACL and MCL fibroblasts. The concentration of aFGF hada significant effect on the proliferation of both ACL and MCL fibroblasts. The concentration of 1 ng/ml bFGF and 5 ng/ml EGF was most effective in promoting the proliferation of ACL, and both bFGF and EGF had a significant effect on MCL. 5ng/ml aFGF with 50 ng/ml EGF had effect on ACL. 1 ng/ml aFGF with 3.13 ng/ml EGF had effect on MCL. Conclusion The three growth factors may promote the cell proliferation of ACL and MCL. These findings suggest that topical application of aFGF, either alone or in combination with EGF may have the potential to promote the proliferation of rabbit ACL and MCL,and aFGF of low concentration in combination with EGF is more effective than single growth factor.
Objective To study the effect of platelet-rich plasma (PRP) on repairing chronic wounds of lower l imbs. Methods From May 2007 to November 2007, 47 patients suffering from chronic wounds of lower l imbs were treated. There were 41 males and 6 females, aged from 15 to 68 years (43.2 years on average). The disease was caused by tibiofibulafracture in 20 cases, calcaneus fracture in 4 cases, metatarsal fracture in 1 case, multiple open fracture of lower l imbs in 3 cases, tibia osteomyel itis in 10 cases, femur osteomyel itis in 1 case, soft tissue injury of ankle in 4 cases, infection after amputation in 2 cases, infection after foot orthomorphia in 1 case, and infection after calcaneus tendon neoplasty in 1 case. Their chronic wounds did not healed after 2 to 4 months of therapy. Among them, chronic wounds compl icated with fracture nonunion in 23 cases and positive bacterial culture result in 38 cases. Debridement and autogenous PRP gel injection were appl ied every 2 months and for twice. Results The patients were followed up for 4 months after the first PRP injection. Two months after the first PRP injection, chronic wounds contracted significantly in 34 patients with purulence and necrosis tissue cleaned up, circulation of soft tissue improved and exposed bone or muscle tissue covered by neogenetic granulation. No patient was completely cured. Two months after the second PRP injection, the average coverage rate was 79.3% ± 18.0%, the total cure rate was 29.8%. The volume of the chronic wounds decreased by (9.3 ± 4.9) mL after PRP therapy (2.5 ± 2.7) mL when compared with (11.8 ± 5.6) mL of before therapy, showing significant difference (P lt; 0.05). X-ray photograph showed that among the 23 cases of fracture nonunion, fracture healed completely in 9 cases; bony callus formation increased obviously in 12 cases; no significant change was observed in 2 cases. No aggravated sign of osteomyel itis was notified. Positive results of bacterial culture reduced to 15 cases. Conclusion PRP efficiently enhances the recovery of soft tissue defect and speeds up the chronic wounds heal ing oflower l imbs.
ObjectiveTo summarize the application status and progress of the strategies to augment tendon-to-bone healing. MethodsThe present researches focused on augmentation of tendon-to-bone healing were extensively reviewed. ResultsThe present strategies to augment healing of tendon-to-bone by enhancing the location environment, and increasing the cell numbers and relative growth factor. The mainly strategies include using calcium phosphate materials, biocompatible scaffolds and glue, growth factors, cell matrix, platelet-rich plasma, and periosteum. Although periosteum have been used in clinical and got some possitive effects, the others still not be used in clinical and needs further studies. ConclusionThere are many strategies to enhance the ability of tendon-to-bone healing, which got some positive results, but results of studies were varied. Thus, further fundamental research and clinical studies are required to achieve the best effects.