Opiate Modulates Lymphocyte Trafficking into the CNS in TB Meningitis

描述(申请人提供)：在全球范围内，结核病(TB)仍然是一个主要的公共卫生危机，艾滋病毒的流行极大地加剧了这一危机。临床上，结核分枝杆菌是艾滋病患者最重要的机会致病菌，中枢神经系统感染是结核病最具破坏性的并发症。与艾滋病毒感染的情况一样，药物滥用一直被认为是结核分枝杆菌发病的一个潜在辅助因素。虽然关于阿片类药物对其他细胞内微生物致病作用的研究很多，但对阿片类药物对淋巴细胞转运的影响知之甚少，对阿片类药物对中枢防御系统抗结核分支杆菌的影响也知之甚少。在中枢神经系统内，结核分枝杆菌引起神经炎性反应，但参与这一反应的细胞和介质在很大程度上是未知的。虽然致敏的T淋巴细胞在防御许多中枢神经系统感染中起着关键作用，但T淋巴细胞在包括结核杆菌在内的感染性因素作用下进入大脑的过程尚未被描述。最近，利用表达荧光素酶的转基因小鼠开发了一种新的成像系统，使研究人员能够在多发性硬化症动物模型中定量跟踪T淋巴细胞向中枢神经系统的运输模式。本申请中提出的研究的总体目标是采用这一创新方法来评估阿片类药物依赖对T淋巴细胞进入中枢神经系统的影响，以应对脑内结核杆菌的挑战。这一定量成像系统的使用将使我们能够检验中心假设，即阿片类药物依赖损害了卡介苗(BCG)致敏的T淋巴细胞向中枢神经系统的运输，从而增加了中枢神经系统结核病的严重程度。为了验证这一假说，我们设计了实验，以解决下面概述的两个特定目标：特定目标1：采用一种新的定量成像技术来确定卡介苗致敏的T淋巴细胞是否在分支杆菌感染时进入中枢神经系统。据推测，卡介苗接种后，卡介苗致敏的T淋巴细胞迅速渗入中枢神经系统，从而保护小鼠免受中枢神经结核的侵袭。具体目的2：确定吗啡的应用是否增强了分支杆菌感染的神经发病机制，并损害了T淋巴细胞向中枢的转运。利用上述中枢神经系统TB范式和T细胞成像技术，将阐明吗啡给药在神经发病机制中的作用。假设吗啡依赖会加速死亡，增加感染对中枢神经系统的损伤，过继转移的卡介苗致敏的T淋巴细胞在吗啡依赖小鼠体内的运输将明显受损。

DESCRIPTION (provided by applicant): Globally, tuberculosis (TB) remains a major public health crisis, which has been dramatically fueled by the HIV epidemic. Clinically, Mycobacterium tuberculosis is the most important opportunistic pathogen in AIDS patients, and infection of the central nervous system (CNS) is the most devastating complication of TB. As in the case of HIV infection, drug abuse has been regarded as a potential cofactor in the pathogenesis of M. tuberculosis. While there have been numerous studies on the effects of opiates on the pathogenesis of other intracellular microbes, little is known about the influence of opiates on lymphocyte trafficking and nothing is known about the impact of opiates on defense of the CNS against M. tuberculosis. Within the CNS, M. tuberculosis elicits a neuroinflammatory response, but the cells and mediators involved in this response are largely undefined. Although sensitized T lymphocytes play a critical role in defense against many CNS infections, the process of T lymphocyte entry into the brain in response to infectious agents, including M. tuberculosis, has not been delineated. Recently, a novel imaging system utilizing transgenic mice expressing luciferase was developed allowing researchers to track quantitatively "in vivo" the trafficking pattern of T lymphocytes into the CNS in an animal model of multiple sclerosis. The overall goal of the research proposed in this application is to adapt this innovative methodology to assess the effects of opiate dependence on T lymphocyte trafficking into the CNS in response to intracerebral challenge with tubercle bacilli. The use of this quantitative imaging system will allow us to test the central hypothesis that opiate dependence impairs the trafficking of Bacille-Calmette-Gu¿rin (BCG)-sensitized T lymphocytes into the CNS thereby increasing the severity of CNS TB. To test this hypothesis, experiments have been designed which address the two specific aims outlined below: Specific aim 1: Adapt a novel quantitative imaging technique to determine whether BCG- sensitized T lymphocytes traffic into the CNS in response to mycobacterial infection. It is hypothesized that BCG vaccination will protect mice against CNS TB through a rapid infiltration of BCG- sensitized T lymphocytes into the CNS following ic inoculation of tubercle bacilli. Specific aim 2: Determine whether morphine administration enhances the neuropathogenesis of mycobacterial infection and impairs T lymphocyte trafficking into the CNS. Using the CNS TB paradigm above and T cell imagining technology, the effects of morphine administration on the neuropathogenesis will be elucidated. It is hypothesized that morphine dependence will accelerate mortality and increase CNS damage due to infection and that the trafficking of adoptive transferred BCG- sensitized T lymphocytes will be markedly impaired in morphine-dependent mice.