Growth Factor and Antiapoptotic Gene Delivery to Human Islets

描述（由申请人提供）：人胰岛移植作为治疗胰岛素依赖型糖尿病的有效手段具有巨大潜力。原发性无功能是胰岛移植失败的主要原因，它导致需要多供体移植。我们将检验这样的假设：通过表达生长因子基因（如促进胰岛血运重建的人血管内皮生长因子（hVEGF））和抗细胞凋亡基因（如人白细胞介素-1受体拮抗剂（hIL-IRa））可以同时增强胰岛植入，以防止宿主中移植的胰岛细胞凋亡。 在初步研究中，较高水平的hVEGF从用编码hVEGF和绿色荧光蛋白的双顺反子腺病毒载体（Acv-GFP-hVEGF）转染的人胰岛分泌，而从Adv-GFP转染和模拟转染的胰岛分泌hVEGF非常低。 转染胰岛的胰岛素释放与模拟转染胰岛相当。当用Adv-GFP-hVEGF转染胰岛时，促凋亡细胞因子IFN-γ和TNF-α不诱导凋亡。 我们的具体目标是确定i）编码hVEGF和hIL-IRa的腺病毒载体（AdvhVEGF-hIL-1 Ra）是否将有效地转染胰岛并改善其功能;和ii）用Adv-hVEGF-hIL-1 Ra离体转染是否将预防原发性胰岛无功能并减少恢复正常所需的胰岛质量。这项研究的意义在于，所提出的离体基因治疗将促进胰岛血管再生，防止凋亡，并减少达到正常血糖所需的胰岛数量。这些数据将有助于成功的人胰岛移植。

DESCRIPTION (provided by applicant): Transplantation of human islets has great potential as an effective means of treating insulin dependent diabetes mellitus. Primary non-function is the main cause of islet graft failure and it results in the need for multi-donor transplants. We will test the hypothesis that islet engraftment can he enhanced simultaneously by expressing growth factor gene like human Vascular Endothelial Growth Factor (hVEGF) that promotes islet revascularization, and antiapoptotic gene like human interleukin-1 receptor antagonist (hIL-IRa) to prevent apoptosis of transplanted islets in the host. In preliminary studies, higher levels of hVEGF were secreted from human islets transfected with bicistronic adenoviral vector encoding hVEGF and Green Fluorescent Protein (Acv-GFP-hVEGF), while hVEGF secretion from Adv-GFP transfected and mock-transfected islets was very low. Insulin release from transfected islets was comparable to mock-transfected islets. Proapoptotic cytokines IFN-gamma and TNF-alpha did not induce apoptosis when islets were transfected with Adv-GFP-hVEGF. Our specific aims are to determine whether i) adenoviral vectors encoding hVEGF and hIL-IRa (AdvhVEGF- hlL-lRa) will efficiently transfect islets and improve their function; and ii) ex vivo transfection with Adv-hVEGF-hlL-IRa will prevent primary islet nonfunction and reduce the islet mass needed for restoring normoglycemia. The significance of this research is that the proposed ex vivo gene therapy will promote islet revascularization, prevent apoptosis and decrease the number of islets required for achieving normoglycemia. The data will be beneficial to successful human islet transplantation.