Grafting of genetically manipulated swine neural system stem cells into Parkinsonian rat brain

本研究的目的是评价猪中枢神经系统干细胞作为替代供体材料的价值，并探讨其遗传学可利用性、异种移植的可能性和神经回路重建。本实验拟将E17- 18猪中脑神经板组织移植到帕金森病大鼠纹状体内，对其进行组织学、免疫化学、电镜观察，并对苯丙胺诱导的旋转恢复进行评价，结果表明，移植物经免疫抑制剂处理后，几乎全部存活4- 12周（FK 506; 1 mg/kg/天im，Endoxane ; 10 mg/kg/天ip），直至2周。免疫组化结果显示。6周大鼠脑移植物内可见大量未成熟细胞、猪特异性神经丝和甲状腺素羟化酶阳性细胞形成玫瑰花结。电镜观察发现，大鼠脑内存在猪特有的神经丝和甲状腺羟化酶阳性神经细胞，参与突触的形成，并观察到许多神经丝阳性神经突起和髓鞘，提示E17-18猪中脑神经板组织可用于异种移植。因此，我们制定了将这些细胞移植到帕金森病猴脑中的研究计划，希望这项研究有助于人类帕金森病治疗的发展。

The purpose of this research are the evaluation of swine CNS stem cells as a substitutional donor material and investigation of the genetic availability, xenografical possibility, and neuronal circuit reconstruction of the CNS stem cells. For those examination, We made a plan to graft E17-l8 swine mesencephalic neural plate tissue into Parkinsonian rat striatum, and we observed them histologically, immunohistochemically, and electron microscopically, and eva1uated them in the respect of the recovery of amphetamine-induced rotation.As a result, almost all graft were survived for 4-l2weeks after transplantation, treating with immunosupressants(FK506 ; 1mg/kg/day im, Endoxane ; 1Omg/kg/day ip) until 2weeks. In the result of immunohistchemical study. we found a lot of rosette formation of immature cells, swine specific neurofilament and thyrosine hydroxylase positive cells in the graft of 6weeks rat brain. In the electron microscopic study, we found swine specific neurofilament and thyrosine hydroxylase positive neural cells in the rat brain, contributing with the synaptic formation, and observed many neurofilament positive neurites with myelin.The result suggested that E17-18 swine mesencephalic neural plate tissue should be available for xenografic transplantation. Therefore , we have made a plan of examination of grafting these cells into the Parkinsonian monkey brain, and we hope this study contribute to the development of the therapy of human Pakinson's disease in the future.