Fenjves Elizabeth S, Ochoa M Sofia, Gay-Rabinstein Carlota, Molano R Damaris, Pileggi Antonello, Mendez Armando J, Inverardi Luca, Ricordi Camillo
Diabetes Research Institute, University Of Miami School of Medicine, Miami, FL 33136, USA. Efenjves@ miami.edu
Transplantation. 2004 Jan 15;77(1):13-8. doi: 10.1097/01.TP.0000110422.27977.26.
The transfer of cytoprotective genes to isolated pancreatic islets may contribute to their enhanced survival in the transplant setting. Our laboratory established the expression of functional erythropoietin (EPO) receptors throughout pancreatic islets. Because EPO is a cytokine that promotes survival, we examined whether adenovirus-mediated gene transfer of EPO would result in cytoprotection of human pancreatic islets in culture and in the transplant setting.
Isolated human islets were transduced using an adenoviral vector coding for human EPO or green fluorescent protein. Comparison of cell death in culture was measured using annexin V-phycoerythrin and propidium iodide. Transplantation of transduced islets into diabetic nude mice was used to assess the effect of EPO on islet function and in vivo survival.
Adenoviral delivery of EPO to pancreatic islets resulted in high-level EPO synthesis and secretion, which did not affect islet function in vitro or in vivo. Islets transduced with EPO were protected from apoptosis in culture and were at a functional advantage in vivo when compared with islets transduced with green fluorescent protein or untransduced islets. The high level of EPO had a negative effect on the blood chemistry of the animals that underwent transplantation.
Overexpression of EPO protects islets from destruction and does not compromise islet function. Genetic engineering with EPO may be a viable approach for improving islet survival and engraftment in the transplant setting, but regulation of the gene's expression will be an important prerequisite to this strategy.
将细胞保护基因导入分离的胰岛可能有助于其在移植环境中提高存活率。我们实验室在整个胰岛中建立了功能性促红细胞生成素（EPO）受体的表达。由于EPO是一种促进存活的细胞因子，我们研究了腺病毒介导的EPO基因转移是否会在培养和移植环境中对人胰岛起到细胞保护作用。
使用编码人EPO或绿色荧光蛋白的腺病毒载体转导分离的人胰岛。使用膜联蛋白V-藻红蛋白和碘化丙啶测量培养物中的细胞死亡情况。将转导后的胰岛移植到糖尿病裸鼠体内，以评估EPO对胰岛功能和体内存活的影响。
将EPO通过腺病毒递送至胰岛导致高水平的EPO合成和分泌，这在体外或体内均不影响胰岛功能。与用绿色荧光蛋白转导的胰岛或未转导的胰岛相比，用EPO转导的胰岛在培养中免受凋亡影响，并且在体内具有功能优势。高水平的EPO对接受移植的动物的血液化学指标有负面影响。
EPO的过表达可保护胰岛免受破坏且不损害胰岛功能。用EPO进行基因工程可能是提高移植环境中胰岛存活率和植入率的可行方法，但该基因表达的调控将是该策略的重要前提条件。
