Objective To explore the histological changes of bio-derived bone prepared by different methods after implantation, and to provide the scaffold material from xenogeneic animal for tissue engineering. Methods Theextremities of porcine femur were cut into 0.5 cm×0.5 cm×0.5 cm. Then they were divided into 5 groups according to different preparation methods: group A was fresh bone just repeatedly rinsed by saline; group B was degreased; group C was degreased and decalcificated; group D was degreased, acellular and decalcificated; group E wasdegreased and acellular. All the materials were implantated into femoral muscle pouch of rabbit after 25 kGy irradiation sterilization. The cell counting ofinflammatory cells and osteoclasts, HE and Masson staining, material degradation, collagen and new bone formation were observed at 2, 6, and 12 weeks postoperatively. Results The residue level of trace element in biomaterials prepared by different methods is in line with the standards. All the animals survived well. There were no tissue necrosis, fluid accumulation or inflammation at all implantation sites at each time point. The inflammatory cells counting was most in group A, and there was significant difference compared with other groups(P＜0.05). There was no significant difference in osteoclasts counting among all groups. For the index of HE and Masson staining, collagen and new bone formation, groups C and D were best, group E was better, and groups A and B were worse. Conclusion The degreased, acellular and decalcificated porcine bone is better in degradation,bone formation, and lower inflammatory reaction, it can be used better scaffold material for tissue engineered bone.
OBJECTIVE: To investigate the effects of three-dimentional culture in bioderived material modified by Pluronic F-127 on the growth and function of rabbit periosteal osteoblast in vitro. METHODS: Bio-derived materials were from fresh pig ribs and were modified by Pluronic F-127. Then rabbit periosteal osteoblasts were cultured in bio-derived materials(group A), in the modified bio-derived materials(group B) and on the plastic surfaces as a control (group C), respectively. During a 7-day period, the status of growth, cell viability and alkaline phosphatase(ALP) activity were measured. RESULTS: Osteoblasts attached, elongated and grew well on the modified bio-derived materials. There were no significant difference in osteogenesis and ALP activity between group A and group B(P gt; 0.05). The osteogenesis and ALP activity in groups A, B were less than those in group C (P lt; 0.01). CONCLUSION: Pluronic F-127 can be used for a carrier for bioactive factors to modify bio-derived material.
ObjectiveTo analyze the progress in biological tissue engineering scaffold materials and the clinical application, as well as product development status. MethodsBased on extensive investigation in the status of research and application of biological tissue engineering scaffold materials, a comprehensive analysis was made. Meanwhile, a detailed analysis of research and product development was presented. ResultsConsiderable progress has been achieved in research, products transformation, clinical application, and supervision of biological scaffold for tissue engineering. New directions, new technology, and new products are constantly emerging. With the continuous progress of science and technology and continuous improvement of life sciences theory, the new direction and new focus still need to be continuously adjusted in order to meet the clinical needs. ConclusionFrom the aspect of industrial transformation feasibility, acellular scaffolds and extracellular matrix are the most promising new growth of both research and product development in this field.
Objective To evaluate the osteogenesis of three bio-bone derived materials in repairing segmental bone defects. Methods Sixty Japanese rabbits were made 10 mm radius segmental defects and divided into 5 groups(groups A, B, C ,D and E,n=12). Composite fully deproteinised bone(CFDB, group A), partially deproteinised bone(PDPB, group B), partially decalcified bone(PDCB, group C), autogenous iliac bone graft(group D) and no implant(group E) were implanted into the radius segmental bone defects of rabbits. The specimens were examined after 4, 8, 12 and 24 weeks; the osteogenesis was evaluated through X-ray radiograph and undecalcified solid tissue histological examination.Results The border between the material and host’s bone was distinct after 4 weeks and blurred after 8 weeks; the density of partial edge of the material was similar to that of radii after 12 weeks. The medullary cavity of bone reopened in group B; the density of most defect area was similar to that of the host bone and there was a few high density shadow in group C; the density of most defect area was higher than that of host bone in group A after 24 weeks. There was no significant difference in radiograph scoring between groups A, B and C after 4 weeks and 8 weeks(P＞0.05); the scores of group B and C were higher than that of group A after 12 weeks(P＜0.05); and the scores were arranged as follow: group Dgt;group Bgt; group Cgt;group A after24 weeks(P＜0.05). Bone callusgrew toward defect area and new bone adhered to the material after 4 weeks and 8 weeks; more new bone formed, and the materials were absorbed and degraded with time. The quantity of bone formation was more in group D than in group B andin group B than in group C and in group C than in group A after 24 weeks(P＜0.05).Conclusion PDPB had good osteogenesis in repairing the segmental bone defect, PDCB was inferior to it, both PDPB and PDCB are fit to repair segmental bone defect. Both of them were inferior to autogenous bone.
Objective To evaluate the biocompatibility of a new bone matrix material (NBM) composed of both organic and inorganic materials for bone tissue engineering. Methods Osteoblasts combined with NBM in vitro were cultured. The morphological characteristics was observed; cell proliferation, protein content and basic alkaline phosphatase(ALP) activity were measured. NBM combined with osteoblasts were implanted into the skeletal muscles of rabbits and the osteogenic potential of NBM was evaluated through contraat microscope, scanning electromicroscope and histological examination. In vitro osteoblasts could attach and proliferate well in the NBM, secreting lots of extracellular matrix; NBM did not cause the inhibition of proliferation and ALP activity of osteoblasts. While in vivo experiment of the NBM with osteoblasts showed that a large number of lymphacytes and phagocytes invading into the inner of the material in the rabbit skeletalmuscle were seen after 4 weeks of implantation and that no new bone formation was observed after 8 weeks. Conclusion This biocompat ibility difference between in vitro and in vivo may be due to the immunogenity of NBM which causes cellular immuno reaction so as to destroy the osteogenic environment. The immunoreaction between the host and the organic-inorganic composite materials in tissue engineering should be paid more attention to.
Objective To investigate the latest development of tissue engineeredregenerative medicine in industrialization, with the intention to direct work in practical area. Methods A complete insight of regenerative medicine in industrialization was obtained through referring to update publications, visiting related websites, as well as learning from practical experience. Results The aerial view of the future of regenerative medicine was got based on knowledge of four different tissue engineering projects. Conclusion All present efforts should be devoted to regenerative medicine area meeting the industrialized trends.
To summarize the medium-term cl inical result of bio-derived bone transplantation in orthopedics with tissue engineering technique. Methods From December 2000 to June 2001, 10 cases of various types of bone defect were treated with tissue engineered bone, which was constructed in vitro by allogenous osteoblasts from periosteum (1 × 106/ mL) with bio-derived bone scaffold following 3 to 7 days co-culture. Six men and 4 women were involved in this study, aged from 14 to 70 years with a median of 42 years. Among them, there were 2 cases of bone cyst, 1 case of non-union of old fracture, 6 cases of fresh comminuted fracture with bone defect, and 1 case of chronic suppurative ostemyel itis. The total weight of tissue engineered bone was 3-15 g in all the cases, averaged 7.3 g in each case. Results The wound in all the case healed by first intention. For 7 year follow up, bone union was completed within 3.0 to 4.5 months in 9 cases, but loosening occurred and the graft was taken out 1 year after operation in 1 case. The X-ray films showed that 9 cases achieved union except one who received resection of the head of humerus. No obvious abnormities were observed, and the function of affected l imbs met daily l ife and work. Conclusion Bio-derived tissue engineered bone has good osteogenesis. No obvious rejection and other compl ications are observed in the cl inical appl ication.
OBJECTIVE: To evaluate the cellular compatibility of three natural xenogeneic bone derived biomaterials. METHODS: Three types of natural xenogeneic bone derived biomaterials were made with physical and chemical treatment, composite fully deproteinized bone(CFDB), partially deproteinized bone(PDPB) and partially decalcified bone(PDCB). Three types biomaterials were cocultured with human embryonic periosteal osteoblasts. The cell growth, attachment, cell cycle, alkaline phosphatase activity were detected to evaluate the cellular compatibility to biomaterials. RESULTS: Osteoblasts attached on all three biomaterials and grew well, the effect of three biomaterials on cell proliferation was PDCB gt; PDPB gt; CFDB. The cell cycle was not obviously affected by three biomaterials. The effect of three biomaterials on alkaline phosphatase activity of osteoblasts was PDCB gt; PDPB gt; CFDB. CONCLUSION: CFDB,PDPB,PDCB have good cellular compatibility without cytotoxic and tumorigenicity, CFDB is the best. The three biomaterials can be used as scaffold materials of bone tissue engineering.
Membrane guided tissue regeneration is new biological concept. The basic theory of this concept includes the belief that during the healing process of wound, the different cells will show different speed of cell migration and regeneration in the wound. If an appropriate membrane being placed to form a mechanical barrier, so that only the needed cells can grow into that area and prevent others from going in, thus resulting in the creation of a guided area where the needed cells can undergo proliferation and differentiation under protection in completing an ideal tissue regeneration and repair. In this article, the experimental researches on the application of membrane guided tissue regeneration in the repair of tubular bone defects, skull defects and faciomaxillary defects were reviewed from literatures, and the degradable and non-degradable materials were introduced, particularly. The pros and cons of this method and the materials were evaluated. It is believed that this technique will push forward the progress in bone biology and reconstructive surgery.
To observe the clinical effect and safety of the nano-hydroxyapatite/polyamide 66 (n-HA/PA66) composite in repairing the bone defects due to benign bone tumors. Methods From January 2003 to May 2005, 38 patients (21 males, 16 females; age, 19-58 years, averaged 38.5 years) with the bone defects due to benign bone tumors were treated with the n-HA/PA66 grains. Among the 37 patients, 11 had fibrous dysplasia, 14 had bone cyst, 10 had giant cell tumor of the bone (Grade Ⅰ), and 2 had enchondroma. The tumors ranged in size from 1.0 cm×0.7 cm×0.4 cm to 10.0 cm×4.0 cm×3.0 cm, with the location of the proximal femur in 12 patients, the distal femur in 7, the proximal tibia in 9, the proximal humerus in 5, the phalanges of the finger in 2, the metacarpal bone in 1,and the calcaneus in 1. Allthe benign bone tumors underwent the curettage treatment, and then the tumor cavities were filled up with the n-HA/PA66 grains. The incision healing, local inflammatory reaction, rejection, toxic reaction, tumor cavity healing, and function recovery of the limbs were all observed after operation. Results All the patients were followed up for 5-33 months, and all the incisions healed by the first intention except 1 incision, which developed infection. The inflammatory reaction was mild, with no reection or general toxic reaction. At 3 to 5.5 months(mean 4 months) after operation, osteogenesis wasfound in the space filled with the n-HA/PA66 grains. Eight months after operation, the patients’ lower limbs could bear weights; 5 months after operation, the upper limbs could complete daily work. Conclusion The n-HA/PA66 grains have great biological safety, good biocompatibility, and good bone conduction, which aregood materials for the bone repair and reconstruction, and can be safely, andeffectively used for repairing the bone defects due to benign bone tumors．