Novel growth factors and regenerative RGC subtypes for optic nerve regeneration

项目摘要或摘要 在哺乳动物视神经损伤后，视网膜神经节细胞（RGC）不能再生其轴突， 很快经历凋亡性细胞死亡，导致永久性视力丧失。一定程度的视神经再生 可以通过实验诱导，但迄今为止实现的再生程度仍然远离 需要视觉功能恢复，需要更有效的治疗。除了测试良好 已建立的生长因子和几种新因子的偶然发现， 然而，许多营养因子和趋化因子受体的未经测试的配体在成人RGCs中表达， 使再生能力大大超过目前可达到的水平。在最近的遗传学研究（RNA-Seq，FACS- 纯化的细胞），我们已经获得了广泛的生长因子，趋化因子和肽受体， 在成人RGC中表达，其许多配体尚未测试对轴突再生的影响， RGC保护。为了进行筛选，我们将使用成人RGC培养系统和体内视神经 再生模型已经在我们的实验室使用了20年，这使我们能够确定三个 以前未知的有效因素的视神经再生。拟议的研究将筛选配体， 成人RGCs中表达的多种受体，以发现视神经再生的新因素 RGC的生存。随着自动化细胞培养系统的显著改进，Aim 1将进行体外细胞培养。 生物活性筛选和体内验证命中。目标2将筛选哪些RGC亚型有反应 到已知的有效治疗和新的命中目标1。这将使我们能够开发组合 治疗同时刺激多种RGC亚型的轴突再生。通过这些研究， 我们期望促进轴突生长的水平比目前和最终所能达到的要高得多。 使我们更接近于改善视神经损伤后的视觉功能。

Project Abstract or Summary Following injury to the optic nerve in mammals, retinal ganglion cells (RGCs) cannot regenerate their axons and soon undergo apoptotic cell death, leading to permanent vision loss. Some degree of optic nerve regeneration can be induced experimentally but the extent of regeneration achieved to date remains away from the level of visual functional recovery required, pointing to the need for more effective therapies. Aside from testing well established growth factors and chance discoveries of several novel factors, a more systematic screening of as yet untested ligands to the many trophic factor and chemokine receptors that are expressed in adult RGCs could augment regeneration well beyond currently achievable levels. In recent genetic studies (RNA-Seq, FACS- purified cells), we have obtained an extensive list of growth factor, chemokine and peptide receptors that are expressed in adult RGCs, many of whose ligands have not been tested for effects on axon regeneration and RGC protection. To carry out the screening, we will use an adult RGC culture system and in vivo optic nerve regeneration models that have been used on our lab for 2 decades, and which have enabled us identify three previously unknown potent factors for optic nerve regeneration. The proposed studies will screen the ligands to the multiple receptors that are expressed in adult RGCs to discover novel factors for optic nerve regeneration and RGC survival. With significantly improved automated cell culture system, Aim 1 will carry out an in vitro bioactivity screen and verify hits in vivo, respectively. Aim 2 will screen which subtypes of RGCs are responding to the known effective treatments and the new hits from Aim 1. This will enable us develop combinatorial treatments to stimulate axon regeneration from multiple RGC subtypes simultaneously. Through these studies, we expect to promote considerably greater levels of axon growth than can be attained currently and ultimately bring us closer to improving visual function after optic nerve damage.