Bone Marrow-Derived Stem Cell Transplantation to Retina

描述(申请人提供)：视网膜光感受器神经元变性，如老年性黄斑变性(AMD)，是美国最常见的致盲原因。有令人信服的理由相信，视网膜下细胞移植可以用来取代缺失的光感受器神经元。目前还没有有效和实用的移植细胞来源。该项目的目标是开发用于移植的细胞，以取代AMD和相关疾病的光感受器神经元。骨髓来源的干细胞作为一种可能的供体细胞来源，与其他类型的细胞相比具有许多优势。这些细胞可以分化为神经元。它们很容易获得，如果用于自体视网膜移植，它们将不会有使用其他类型细胞所固有的免疫学后果。据我们所知，没有其他实验室正在研究将骨髓来源的干细胞移植到视网膜。目前，还没有证据表明骨髓干细胞可以分化为视网膜神经元。这项初步研究的具体目的是确定允许这些细胞分化为光感受器神经元或其他视网膜细胞类型的条件。这项研究有三个连续的步骤。首先，以可能诱导光感受器表型的方式处理GFP标记的骨髓来源干细胞。这包括在成纤维细胞生长因子-2、表皮生长因子、维甲酸、声波刺猬和牛磺酸等因子中培养细胞，和/或将光感受器细胞特异性转录因子CRX的基因导入细胞。其次，将骨髓干细胞与胚胎视网膜共培养，或将细胞移植到光感受器细胞耗尽的动物的视网膜下空间。第三，通过测定骨髓干细胞在宿主视网膜中的板层分布，并用针对视网膜细胞类型的抗体进行免疫组化，从组织学上评估骨髓干细胞在视网膜共培养中或移植到视网膜后的分化情况。

DESCRIPTION (provided by applicant): Degeneration of retinal photoreceptor neurons, such as that seen in age-related macular degeneration (AMD), is the most common cause of blindness in the United States. There are compelling reasons to believe that subretinal cell transplantation could be used to replace missing photoreceptor neurons. No effective and practical source of cells for transplantation is currently available. The goal of this project is to develop cells to be used for transplantation to replace photoreceptor neurons in AMD and related diseases. Bone marrow-derived stem cells offer numerous advantages over other cell types as a possible source of donor cells. These cells can differentiate into neurons. They are readily available, and if used for autologous transplantation to the retina, they would not have the same immunological consequences inherent in the use of other cell types. To our knowledge, no other laboratories are investigating bone marrow-derived stem cells for transplantation to the retina. At this time, there is no evidence that bone marrow-derived stem cells can differentiate into retinal neurons. The specific aim of this preliminary investigation is to determine conditions that would allow these cells to differentiate as photoreceptor neurons or other retinal cell types. The study has three sequential steps. First, treat GFP-labeled, bone marrow-derived stem cells in ways likely to induce the photoreceptor phenotype. This includes culturing cells in factors such as FGF-2, EGF, retinoic acid, sonic hedgehog and taurine, and/or transfecting the cells with a gene for the photoreceptor cell specific transcription factor, Crx. Second, co-culture treated bone marrow-derived stem cells with embryonic retina or transplant the cells to the subretinal space in animals depleted of photoreceptor cells. Third, assess histologically the differentiation of bone marrow-derived stem cells in the retinal co-cultures or after transplantation to the retina by determining their laminar distribution in the host retina and by immunohistochemistry with antibodies specific to retinal cell types.