Potassium Channel Trafficking in Geometrically Patterned Immunological Synapses

几何图案免疫突触中的钾通道运输

• 批准号: 7659936
• 负责人: LAURA CONFORTI
• 金额: $ 23.4万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-02-15 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7659936
• 关键词: Address; Affect; Antigen-Presenting Cells; Antigens; Autoimmune Diseases; Autoimmune Process; Calcium; Carbon; Cell Communication; Cell membrane; Cell physiology; Cell surface; Cells; Complex; Data; Development; Disease; Electrodes; Engineering; Event; Gold; Image; Immune response; Immune system; Immunosuppressive Agents; Ion Channel; Kv1.3 potassium channel; Laboratories; Ligands; Location; Lymphocyte; Lymphocyte Function; Measurement; Membrane; Membrane Proteins; Methods; Microscopy; Molecular; Monitor; Nanotechnology; Outcome; Patients; Pattern; Play; Positioning Attribute; Potassium Channel; Process; Protein Engineering; Proteins; Regulation; Role; Series; Signal Transduction; Signaling Molecule; Spectrum Analysis; Structure; Surface; Synapses; Systemic Lupus Erythematosus; T-Cell Activation; T-Cell Receptor; T-Lymphocyte; Techniques; Testing; Viral Tumor Antigens; Work; cancer cell; college; design; electric impedance; electrical property; functional outcomes; immunological synapse; immunological synapse formation; interest; novel; pathogen; public health relevance; response; sialosyl-T antigen; trafficking; voltage clamp

DESCRIPTION (provided by applicant): Lymphocytes respond to antigens with a series of events that constitute the T cell activation process. T cell activation is necessary and beneficial when the antigen is a pathogen or a cancer cell, but it becomes undesirable when the immune system identifies components of the body's own cells as foreign. This aberrant response occurs in autoimmune diseases. Thus studying the activation process of normal and autoimmune T cells is of primary importance. T cell activation is initiated by contact of the T cell with the antigen presenting cell (APC) and formation of the immunological synapse (IS). The IS is a highly organized signaling zone that forms at the T/APC interface and is needed for full development of the activation response. Although various aspects of the process of IS formation have been thoroughly investigated, the underlying membrane ionic events are poorly understood. Kv1.3 potassium channels are expressed in T cells where they compartmentalize together with the T cell receptor complex and various signaling molecules at the IS. Kv1.3 channels play an important role during T cell activation as they regulate the Ca2+ influx necessary for downstream functional events. Indeed, inhibition of these channels terminates the immune response and therefore Kv1.3 blockers are under development as novel immunosuppressive agents. Despite the significance of these channels, the functional consequences of their compartmentalization in the IS of T cells are yet to be determined. Preliminary data from our laboratory suggest that Kv1.3 location within the IS is necessary to regulate the channel function and alterations in Kv1.3 channel localization in the IS have been observed in the autoimmune disease SLE. In this application we will be testing the hypothesis that Kv1.3 channels' recruitment in the immunological synapse and their specific location within this structure is necessary for regulation of the channel activity and consequently it influences the outcome of T cell activation. Specifically we will engineer artificial APC-like surfaces allowing targeted sequestration of Kv1.3 proteins in a predetermined location within the IS and simultaneous measurement of downstream functional events. These studies will establish the feasibility of engineered protein surfaces for studying ion channel compartmentalization in the IS, specifically addressing the question of how the position of ion channels in the IS determines the outcome of T cell/APC interactions. Furthermore, these studies will enable understanding of the implications that abnormalities in ion channel recruitment into the IS have on overall T cell function in pathological conditions. PUBLIC HEALTH RELEVANCE: Lymphocytes function, and also therefore malfunction, is in part controlled by Kv1.3 channels in the cell membrane. We are interested in studying details of how the location of Kv1.3 channels in the contact point between T cells and antigen presenting cells affects the channels' function. To do this we propose a novel method combining nanotechnology and artificial antigen presenting cell-like surfaces.

描述（由申请人提供）：淋巴细胞通过一系列构成 T 细胞激活过程的事件对抗原做出反应。当抗原是病原体或癌细胞时，T 细胞激活是必要且有益的，但当免疫系统将人体自身细胞的成分识别为外源时，T 细胞激活就变得不可取。这种异常反应发生在自身免疫性疾病中。因此，研究正常和自身免疫 T 细胞的激活过程至关重要。 T 细胞激活是通过 T 细胞与抗原呈递细胞 (APC) 接触并形成免疫突触 (IS) 来启动的。 IS 是一个高度组织化的信号区域，形成于 T/APC 界面，是激活反应全面发展所必需的。尽管 IS 形成过程的各个方面已得到彻底研究，但对潜在的膜离子事件知之甚少。 Kv1.3 钾通道在 T 细胞中表达，在 T 细胞中与 T 细胞受体复合物和 IS 处的各种信号分子一起划分。 Kv1.3 通道在 T 细胞激活过程中发挥重要作用，因为它们调节下游功能事件所需的 Ca2+ 流入。事实上，抑制这些通道会终止免疫反应，因此 Kv1.3 阻滞剂正在开发作为新型免疫抑制剂。尽管这些通道很重要，但它们在 T 细胞 IS 中划分的功能后果仍有待确定。我们实验室的初步数据表明，Kv1.3 在 IS 内的定位对于调节通道功能是必要的，并且在自身免疫性疾病 SLE 中观察到了 IS 中 Kv1.3 通道定位的改变。在此应用中，我们将测试以下假设：Kv1.3 通道在免疫突触中的募集及其在该结构中的特定位置对于通道活性的调节是必要的，因此它会影响 T 细胞激活的结果。具体来说，我们将设计类似 APC 的人工表面，从而将 Kv1.3 蛋白定向隔离在 IS 内的预定位置，并同时测量下游功能事件。这些研究将确立工程蛋白质表面用于研究 IS 中离子通道区室化的可行性，特别是解决 IS 中离子通道的位置如何决定 T 细胞/APC 相互作用的结果的问题。此外，这些研究将有助于了解离子通道募集异常对病理条件下 T 细胞整体功能的影响。 公共健康相关性：淋巴细胞的功能以及因此产生的故障部分由细胞膜中的 Kv1.3 通道控制。我们感兴趣的是研究 Kv1.3 通道在 T 细胞和抗原呈递细胞之间接触点的位置如何影响通道功能的细节。为此，我们提出了一种结合纳米技术和人工抗原呈递细胞样表面的新方法。