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Research paper : Development of regenerative medical technology working toward practical application (H. Ohgushi)−158 Synthesiology - English edition Vol.1 No.3 (2009) Verification of bone differentiation ability in biomaterial used was accomplished by in vitro culture and in vivo transplantation. We developed an evaluation technique that allows predictable determination of efficacy of biomaterial used in bone regenerative medicine.3.4 Standards for regenerative medicineAs described above, in regenerative medicine, it is necessary to constantly verify the efficiency of cultivation process as well as check whether the harvested cells, cultured and grown cells, and differentiated cells are performing properly. Considering commercialization of regenerative medicine, it is mandatory to establish the evaluation method as standards for safety and efficacy of the cells used. The standard for evaluation result is built by employing standardized cell evaluation method, and determination of safety and efficacy can be done readily. Standardization will clarify the indices for increasing efficiency of the process, and this will promote designing and production of regenerative medical products. As mentioned in Section 3.3, we are in the process of establishing the evaluation method of biomaterial used in bone regeneration medicine. Therefore, we are considering international standardization of the evaluation method. Currently, about 230 Technical Committees (TC) are active in the International Organization for Standardization (ISO), and TC150 (Implants for Surgery) is in charge of medical devices. TC150 is further broken down into Subcommittees (SC) and Working Groups (WG) where specialists from around the world engage in discussion. For regenerative medicine, standardization proposal for regenerative medical technologies were discussed in WG11 (Tissue Engineered Implants), and in January 2007, the working group was “promoted” to SC7 (Tissue Engineered Medical Products). We submitted the proposal “In vivo bone formation in porous materials using rat mesenchymal cell − Standardization to evaluate bone forming ability of biomaterials,” to commence activities toward regenerative medical technology standardization originating from Japan. Figure 5 shows the bone formation in the material conducted according to the proposal.4 Clinical application of regenerative medical technologyWe conducted various technological developments with corporate partners to overcome issues in regenerative medicine. As result, we succeeded in implanting artificial joints formed with tissue-engineered bone to osteoarthritis patient for first time in the world. About 6 years have passed since the first case, and there have been more than 50 cases in total. Although the history is short, there had been no side effects such as inflammation or infection, or “loosening” at the implant site, which is adverse event for artificial joints[6]. Tissue-engineered bones were also transplanted to cases of bone tumor[7] as well as arthropathy patients. According to the survey by Fuji Keizai Co., Ltd., there are about 800,000 arthropathy patients in Japan, of which 200,000 patients are estimated to be candidates of regenerative medicine. Our technology is likely to be indicated for many of these patients. Moreover, it was confirmed that MSC could be differentiated into vascular endothelium and cardiac muscle cells[8], and we started clinical application for heart regeneration in collaboration with the National Cardiovascular Center. As described, we succeeded in developing treatments for heart diseases as well as bone and joint diseases by using cells (bone marrow cells) from patients themselves, and these cells were harvested with minimum invasion (bone marrow aspiration) without sacrificing the patients’ tissues. There are estimated 1,600,000 patients with heart disease. Clinical application to wider range of tissue and organ regeneration can be expected by using the cell differentiation ability of mesenchymal cells from bone marrows to various cells and tissues.5 Discussion (future issues)As described above, we developed various technologies for regenerative medicine and have conducted applications or clinical studies in patients with various diseases starting with bone regeneration. However, it is necessary for the companies to spend more effort in medical applications before this technology can benefit patients. The studies must undergo the process of clinical trials, and tissue-engineered cells must be marketed as regenerative medical product after receiving approval of the Ministry of Health, Labour and Welfare. In the United States, Genzyme Corporation markets cultivated chondrocytic (cartilage) cells to over 10,000 patients under approval of the Food and Drug Administration (FDA). In Japan, Professor Ochi of the Hiroshima University conducted 3-dimensional culture of cartilage in collagen gel, and developed the cartilage regeneration technology using this cartilage collagen gel hybrid. This technology was transferred to Japan Tissue Engineering Co., Ltd. (JTEC), and the clinical trials have been almost completed but the product is not yet available. At the same time JTEC started cartilage regeneration, Sewon Cellontech Co., Ltd. of Korea started cartilage regeneration business, received approval of Bone formation after in vivo transplantation (back of rat)Synthetic porous hydroxyapatiteCoral- hydroxyapatitein vivo(4)−Fig. 5 Verification of biomaterials (areas of osteoblasts location after MSCs seeding).

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