Astrocyte-specific ligand discovery by phage display

 描述(由申请人提供)：星形胶质细胞已被认为在可塑性和神经元变性中发挥关键作用。尽管星形胶质细胞数量丰富，具有重要的动态平衡作用，但对星形胶质细胞是如何产生的，以及星形胶质细胞实现特殊功能的机制知之甚少。相比之下，有130多个神经元亚类，关于其中许多谱系的转录网络已经被发现。这在一定程度上是因为人们非常重视对神经元的了解，但也是因为为不同类别的神经元确定的分子和遗传标记的数量。后者促进了特定谱系工具和动物模型的发展，以破译神经元亚型在认知、运动和感觉功能等不同行为中的不同作用。在这里，我们建议利用噬菌体展示筛选方法来鉴定星形胶质细胞和星形胶质细胞亚型的独特分子方面，以加速我们对星形胶质细胞在健康和疾病中的功能的理解。基于细胞的噬菌体筛选是一种强大的技术，它涉及到在不需要特定受体的先验知识的情况下，根据所需的细胞结合特性从超过20亿个唯一的候选多肽序列中选择多肽配体。我们将把我们在胶质发生和胶质细胞生物学方面的专业知识与生物工程、药物筛选和发现方面的专业知识结合起来，开发用于星形胶质细胞细分和体内星形胶质细胞直接成像的新工具。我们提出：目的1.通过噬菌体展示文库筛选星形胶质细胞特异性多肽；目的2.评价星形胶质细胞特异性多肽作为星形胶质细胞群体细胞特异性标志物的价值；3.星形胶质细胞体内成像分子探针的研制。这一提议利用了两个主要调查人员的独特研究能力和他们长期合作的历史。我们期望通过这个拟议的项目开发的工具和技术将通过识别星形胶质细胞的独特生物标记物以及按功能分类的星形胶质细胞亚型来促进胶质生物学的快速发展。

 DESCRIPTION (provided by applicant): Astrocytes have been proposed to play critical roles in plasticity as well as neuronal degeneration. Despite their abundance and key homeostatic roles very little is known regarding how astrocytes are generated and the mechanisms whereby astrocytes achieve specialized functions. In contrast, there are over 130 sub-classes of neurons and the transcriptional network regarding many of these lineages have been discovered. This is in part due to the significant emphasis that has been placed on understanding neurons but also due to the number of molecular and genetic markers that have been identified for different classes of neurons. The latter has facilitated the development of lineage specific tools and animal models to decipher the various roles of neuronal subtypes in divergent behaviors such as cognition, locomotion and sensory function. Here we propose to utilize a phage display screening approach to identify unique molecular aspects of astrocytes and astrocyte subtypes in order to accelerate our understanding of astrocyte function in health and disease. Cell-based phage screening is a powerful technology that involves the selection of peptide ligands from over 2 billion unique candidate peptide sequences based on desired cell binding properties and without a priori knowledge of specific receptors. We will combine our expertise in gliogenesis and glial cell biology with that of bioengineering, drug screening and discovery to develop novel tools for subclassifying astrocytes and also for direct imaging of astrocytes in vivo. We propose: Aim 1. Identification of astrocyte-specific peptides by phage display library selection, Aim 2. Evaluation of astrocyte-specific peptides as cell-specific markers for astrocytic populations and Aim 3. Development of a molecular probe for in vivo imaging of astrocytes. This proposal takes advantage of the unique research capabilities of the two principle investigators and their long-standing collaborative history. We expect that the tools and technologies developed through this proposed project will enable rapid advances in glial biology through the identification of unique biomarkers of astrocytes in general as well as astrocyte subtypes classified by function.