DEVELOPMENT OF ARTIFICIAL TISSUE SCAFFOLD FOR ISLET CELL TRANSPLANTATION

胰岛移植逆转或预防糖尿病的慢性效应在很大程度上是不成功的。其原因尚不清楚，但移植部位血管化不足可能起着重要作用。胰岛细胞移植物如果移植到血管化良好的部位，并提供足够的营养和氧气，则应发挥良好的功能。我们已经报道，当将碱性成纤维细胞生长因子（bFGF）加入到软骨细胞接种的胶原支架中时，软骨组织的再生加速，这可能是因为在移植早期细胞周围毛细血管的快速形成。在这项研究中，一个良好的血管化的人工组织被开发为胰岛细胞移植的支架通过预植入的支架与bFGF和/或成纤维细胞与胰岛接种之前。由于细胞维持在血管化组织内，因此移植所需的细胞数量可能会减少。当使用聚乙交酯布片作为支架时，与单独的成纤维细胞或bFGF相比，当bFGF和成纤维细胞一起植入时，在1周时血管向内生长到支架中更大。2周时血管化的差异不太明显。我们还开发了一种新的脱细胞猪组织的过程中使用的微波辐射下的挤压和洗涤脱细胞支架。在10.000大气压下处理10 mm后，组织完全无细胞。处理后组织的生物力学性能没有显著变化。根据体外培养试验，当对被正常菌群污染的瓣膜施加按压时，组织被消毒。通过分配器成功地将成纤维细胞注射到支架组织中。

Islet transplantation to reverse or prevent the chronic effects of diabetes has been largely unsuccessful. The reasons for this are still unclear, but inadequate vascularization at the transplant site may play an important role. Islet cell grafts should function well if transplanted into well-vascularized sites supplied with sufficient nutrients and oxygen. We have already reported that when basic fibroblast growth factor (bFGF) was added to the collagen scaffold on which chondrocytes were seeded, the regeneration of cartilage tissue was accelerated, probably because of the rapid formation of capillaries around the cells in the early stage of transplantation. In this study, a well-vascularized artificial tissue was developed as a scaffold for islet cell transplantation by preimplantation of a scaffold with bFGF and/or fibroblasts prior to seeding with the islets. Since the cells are maintained inside of the vascularized tissue, the number of cells required for transplantation may be diminished. When a sheet of polyglycoride cloth was used as the scaffold, the vascular ingrowth into the scaffold at I week was greater when bFGF and fibroblasts were implanted together, compared to fibroblasts or bFGF alone. Differences in vascularization at 2 weeks were less apparent. We also developed an acellular scaffold by a novel decellularization process of porcine tissue using an ultrahigh pressing and washing under microwave irradiation. The tissue was completely cell free after this processing of 10.000 atm for 10 mm. There were no significant changes in bioinechanical properties of the tissue treated. From the in vitro incubation test, the tissue was disinfected when the pressing was applied to the valves contaminated by normal bacteria floras. The fibroblasts were successfully injected into the scaffold tissue by the dispenser.