Clarification of promoting effect on engraftment of intraportally transplanted islet cells under hepatic regeneration

目得：为了在单供体胰岛移植后实现成功的胰岛素非依赖性，我们研究了肝再生对术后即刻门静脉内移植胰岛细胞植入的影响。我们证明，肝再生促进功能性植入，并改善胰岛素分泌和移植后高血糖大鼠。本研究的目的是阐明促进作用下肝再生的门静脉内移植的胰岛细胞的植入通过详尽的基因分析使用microarray.METHODS：从一个单一的供体分离的胰岛经门静脉内移植到链脲佐菌素糖尿病大鼠后立即70%部分肝切除术（HxPIT），也移植到大鼠没有肝切除术（PIT）。移植后24小时，从受体大鼠中取出肝脏，然后从肝内移植的胰岛细胞中提取RNA。结果：HxPIT大鼠移植的胰岛细胞体积较大，颗粒状的肥大的β细胞构成了胰岛细胞的颗粒状结构。移植胰岛及胰岛细胞的体积均大于PIT大鼠。基因芯片分析表明，HxPIT大鼠的肝细胞生长因子（HGF）和血管内皮生长因子（VEGF）的表达量明显高于PIT大鼠。未来的发展：我们将利用显微切割技术从移植胰岛中提取RNA，以排除没有移植胰岛细胞的RNA。然后，我们将使用绿色大鼠（绿色荧光蛋白; GFP基因转移大鼠）作为胰岛移植的供体，在荧光显微镜下使用显微切割技术选择性地仅摘除胰岛细胞。

PURPOSE : To achieve successful insulin independence after single-donor islet transplantation, we had examined the impact of hepatic regeneration on engraftment of islet cells transplanted intraportally in the immediate postoperative period. We demonstrated that hepatic regeneration promotes functional engraftment and ameliorates insulin secretion and posttransplantation hyperglycemia in rat. The aim of this study was to clarify promoting effect on engraftment of intraportally transplanted islet cells under hepatic regeneration by exhaustive gene analysis using micro array.METHODS : Isolated pancreatic islets from a single-donor were intraportally transplanted to streptozotocin-diabetic rats immediately after 70% partial hepatectomy (HxPIT) and were also transplanted to the rats without hapatectomy (PIT). The livers were removed from the recipient rats after 24 hours posttransplantation, and then RNA was extracted from intrahepatic engrafted islet cells. We analyzed gene expression of the RNA using rat micro array (Rat Genome 230 2.0 Array).RESULTS : Morphologically, grafted islets from HxPIT rats were large and granulated by hypertrophic beta cells. The sizes of the grafted islets and indivisual insulin-stained islet cells were larger than those from PIT rats. The gene analysis using micro array demonstrated that the expression of hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) of the RNA extracted from HxPIT rats was statistically higher than that from PIT rats.FUTURE EVOLUTION : For the future, we will extract RNA from grafted islets using microdissection technique to exclude most surely the RNA without grafted islet cells. And then, we will use green rats (green fluorescent protein ; GFP gene transfer rats) for the donor in islet transplantation to extirpation selectively only islet cells using microdissection technique under the fluorescent microscope.