The Spread of Noisy Information in Corneal Epithelial Wound Response Signaling

 描述（由申请人提供）：角膜伤口可导致瘢痕形成、模糊和随后的视力丧失。几种生化信号，包括细胞外核苷酸和生长因子在激活伤口愈合程序中起关键作用。伤口诱导信号的分子特性的发现促进了旨在延长自然愈合程序以最小化损伤诱导的视力丧失的危险的疗法的发展。然而，这些治疗方法仅取得了有限的成功。缺乏对这些旁分泌信号分子调节的详细定量机制理解，阻碍了对当前疗法的关键评估和下一代定量系统药理学治疗方法的发展。这项工作的目标是确定控制两个关键的旁分泌信号分子：ATP和HB-EGF的时空传播的调节机制。每一种都在伤口愈合程序的激活中起着至关重要的作用。这项提议将利用我们最近开发的一种新的基于微流体的创伤平台。该新设备能够在没有任何流体混合的情况下高度控制上皮单层的创伤，从而生成Ca 2+和Erk途径时空传播的实时数据。我们将使用新的设备协同多种计算方法来解剖旁分泌信号调节网络，控制伤口诱导信号的传播。具体目的是：（1）阐明ATP起始信号传播的控制机制。(2)剖析负责Erk通路激活的空间传播的机制。(3)确定旁分泌信号在降低Erk通路激活中的噪声中的作用。在目标1和2中，我们将构建并独立校准多尺度组织水平模型，该模型将联合收割机细胞间ATP和HB-EGF动力学与细胞内Ca 2+和Erk途径激活的动力学结合起来。这些模型将用于测试关于控制ATP和HB-EGF信号的时空传播以激活伤口反应信号传导的机制的多个假设。在目标3中，我们将使用信息论方法来分析测试所确定的机制如何有助于生成Erk激活的鲁棒空间分布。这些目标的成功完成将填补关于调节伤口愈合程序激活的复杂机制的重要知识空白。我们将构建和实验证实的预测数学模型将为未来治疗的设计提供重要工具，旨在增强现有的伤口愈合计划，以防止因角膜损伤而导致的视力丧失。

 DESCRIPTION (provided by applicant): Cornea wounds can lead to scarring, hazing, and subsequent vision loss. Several biochemical signals, including extracellular nucleotides and growth factors play key roles in activation of wound healing programs. The discoveries of the molecular identities of wound induced signals prompted the development of therapies that aim to prolong the natural healing programs in order to minimize the danger of injury induced vision loss. However, these therapeutic approaches had only limited success. The lack of a detailed quantitative mechanistic understanding of the regulation of these paracrine signaling molecules prevents the critical assessment of current therapies and the development of the next generation of quantitative systems pharmacology therapeutic approaches. The goal of this work is to determine the regulatory mechanism that controls the spatio-temporal propagation of two key paracrine signaling molecules: ATP and HB-EGF. Each plays an essential role in the activation of wound healing programs. This proposal will capitalize on a novel microfluidics-based wounding platform we recently developed. The new device enables highly controlled wounding of epithelial monolayers without any fluid mixing and thereby generates real-time data of the spatio-temporal propagation of the Ca2+ and Erk pathways. We will use the new device in synergy with multiple computational approaches to dissect the paracrine signaling regulatory network that controls the propagation of wound induced signals. The specific aims are: (1) Elucidate the mechanism that controls the spread of initial ATP signals. (2) Dissect the mechanisms responsible for the spatial propagation of Erk pathway activation. (3) Determine the function of paracrine signals in reducing the noise in Erk pathway activation. In aims 1 and 2 we will construct and independently calibrate multi-scale tissue-level models that combine intercellular ATP and HB-EGF dynamics with intracellular the kinetics of Ca2+ and Erk pathway activation. The models will be used to test multiple hypotheses on the mechanism that controls the spatio-temporal propagation of ATP and HB-EGF signals to activate wound response signaling. In aim 3 we will use an information-theory approach to analyze test how the identified mechanisms contribute to the generation of a robust spatial distribution of Erk activation. The successful completion of these aims will close an important knowledge gap on the complex mechanism that regulates the activation of wound healing programs. The predictive mathematical models that we will construct and experimentally corroborate will provide an important tool in the design of future therapies that aim to augment existing wound healing programs to prevent vision loss due to corneal injury.