Development of New device for Regeneration of small intestinal tissue

1. 用于小肠组织再生的新型聚乳酸管（或聚乙醇酸）的研制。我们完成了适用于小肠再生的新型聚乳酸（或聚乙醇酸）管。我们还发现bFGF是小肠组织再生中最有用的生长因子。因此，我们完成了可生物降解的明胶微球，它可以连续释放bFGF。我们将这些微球附着在试管内部，并将骨髓细胞注射到这个试管中（我们称之为小肠再生管=SIR管）。我们将SIR管移植到已切除小肠的大鼠小肠进行实验。有趣的是，移植2个月后，在SIR管内观察到小肠组织的再生。对再生小肠组织进行组织学和功能检查。结果，微小的内窥镜检查显示移植后一个月出现绒毛上皮。此外，我们还研究了再生小肠中免疫调节细胞的比例。组织学和FACS分析显示再生小肠中巨噬细胞、T细胞和B细胞的比例与正常小肠无显著差异。我们在SIR管中注射GFP骨髓细胞。移植该管3个月后，我们观察了GFP骨髓细胞在再生小肠中分化成何种细胞。结果共聚焦显微镜观察显示，GFP在肌成纤维细胞和小肠上皮中呈阳性，提示移植骨髓细胞分化为上皮细胞和间充质细胞，构成了新生小肠。

1. Development of innovative polylactic acid tube (or polyglycolic acid) for regenerating small intestinal tissue. We have completed innovative polylactic acid (or polyglycolic acid) tube which could be suitable for regeneration of small intestine. We also showed that bFGF is most useful growth factor for regeneration of small intestinal tissue. Therefore, we completed the biodegradable gelatin microspheres, which can continuously release bFGF. We attached these microspheres to inside of the tube and injected bone marrow cells into this tube (we named it as small intestinal regenerating tube=SIR tube.). We transplanted SIR tube to small intestine of rat, which had taken resection of small intestine for experiment. Interestingly, regeneration of small intestinal tissue was observed inside of SIR tube 2 months after transplanting.2. We checked regenerated small intestinal tissue histologically and functionally. As a result, minute endoscopic findings revealed that villous epithelium was appeared one month after transplanting.3. Moreover, we investigated the proportion of immune-regulating cells in regenerated small intestine. Histological and FACS analysis revealed that there was no significant difference of the proportion of macrophages, T, and B cells in between regenerated and normal small intestine.4. We injected GFP bone marrow cells in SIR tube. Three months after transplanting this tube, we investigated what kinds of cell GFP bone marrow cells would differentiate into in regenerated small intestine. As a result, confocal microscopic findings showed that GFP was positive for myofibroblasts and small intestinal epithelium, which suggested that transplanted bone marrow cells differentiated into epithelium and mesenchymal cells and compose of newly regenerated small intestine.