Transport of TNFalpha across the BBB

TNFα 跨 BBB 的转运

• 批准号: 6726355
• 负责人: Weihong Pan
• 金额: $ 5.42万
• 依托单位: TULANE UNIVERSITY OF LOUISIANA
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-01-01 至 2004-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6726355
• 关键词: autoradiography; biological transport; blood brain barrier; chordate locomotion; cytoskeletal proteins; evoked potentials; gene targeting; genetically modified animals; immunoprecipitation; laboratory mouse; molecular chaperones; nervous system regeneration; neural conduction; oncogenes; phosphorylation; polymerase chain reaction; proteomics; receptor; receptor expression; spinal cord injury; transfection; transport proteins; tumor necrosis factor alpha; western blottings

DESCRIPTION (provided by applicant): The blood-brain and blood-spinal cord barriers (BBB/BSCB), lying between the CNS (brain and spinal cord) and its supplying capillary blood vessels, provide an immense interface for interaction and exchange of information between the CNS and the rest of the body. We have shown that the BSCB is not static or physically passive, but undergoes dynamic changes, to regulate the availability of the cytokine tumor necrosis factor a (TNFa) from blood to the CNS. In the proposed studies, we will test the hypothesis that TNFa, after being transported across the BBB/BSCB, can facilitate functional recovery after spinal cord injury (SCI). We will also characterize the mechanisms by which this specific transport can be regulated. To determine the functional implications of TNFe transport, we will first show that spinal cord uptake of radioactively labeled TNFe will increase specifically in a modified mouse model of thoracic hemisection, and that this increase will not coincide with passive disruption of the barrier (measured by increased paracellular permeability of albumin). We will then determine the effects of TNFa treatment by evaluating locomotor behavior, intraspinal conduction of evoked potentials, and histological evidence of long tract regeneration. We expect that small doses of TNFa will facilitate recovery whereas large doses will worsen the deficits resulting from SCI. To identify the roles of p55- and p75-receptors, we will study TNFa transport in the presence of receptor antibodies and in the receptor knockout mice. We predict that increased spinal cord uptake of TNFe after SCI will be dependent upon upregulation of the receptors, as determined by Western blot and quantitative PCR analysis. Since transcytosis of a cytokine across the BBB/BSCB is a complicated process involving not only the receptors but also other regulatory proteins, we will identify novel transport regulatory proteins by co-immunoprecipitation, comparative proteomics, transfection and transport assays. We predict that the transport process will be regulated by the receptors, vesicular and cytoskeletal proteins, and chaperons in different phosphorylation states. By completing the proposed study, we will better understand the dual roles of TNFa in SCI and in its transport process involving the regulatory proteins. These transporters could be novel drug targets and therefore provide promising therapeutic potential.

描述（由申请人提供）：位于中枢神经系统（脑和脊髓）之间的血脑和脊髓屏障（BBB/BSCB）及其供应毛细血管血管之间，为CNS与身体其他部分之间的信息提供了巨大的界面。我们已经表明，BSCB不是静态的或物理上的，而是经历动态变化，以调节细胞因子肿瘤坏死因子A（TNFA）从血液到CNS的可用性。在拟议的研究中，我们将检验以下假设：TNFA在跨BBB/BSCB进行运输后可以促进脊髓损伤（SCI）后的功能恢复。我们还将表征可以调节这种特定运输的机制。为了确定TNFE传输的功能含义，我们首先表明，脊髓的脊髓吸收tnfe的脊髓吸收将在修饰的胸部半分配的小鼠模型中特别增加，并且这种增加不会与屏障的被动破坏（通过通过增加的白蛋白的副细胞渗透性来衡量）。然后，我们将通过评估运动性行为，诱发电位的脊柱内传导以及长道再生的组织学证据来确定TNFA治疗的影响。我们预计，一小剂量的TNFA将有助于恢复，而大剂量会使SCI导致的缺陷恶化。为了确定p55和p75受体的作用，我们将在受体抗体存在和受体敲除小鼠中研究TNFA转运。我们预测，通过蛋白质印迹和定量PCR分析确定，SCI后TNFE的脊髓吸收增加将取决于受体的上调。由于跨BBB/BSCB的细胞因子的转胞膜不仅是一个复杂的过程，不仅涉及受体，而且还涉及其他调节蛋白，因此我们将通过共免疫沉淀，比较蛋白质组学，转染和运输分析来鉴定新型的运输调节蛋白。我们预测，转运过程将受受体，囊泡和细胞骨架蛋白以及不同磷酸化状态的伴侣蛋白的调节。通过完成拟议的研究，我们将更好地了解TNFA在SCI中的双重作用以及其涉及调节蛋白的运输过程中的双重作用。这些转运蛋白可能是新型的药物靶标，因此具有有希望的治疗潜力。