L-citrulline and anti-tuberculosis host defense

L-瓜氨酸和抗结核宿主防御

• 批准号: 9304965
• 负责人: Joseph E Qualls
• 金额: $ 39万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9304965
• 关键词: Address; Amino Acids; Antibiotic Therapy; Antibiotics; Antitubercular Agents; Arginine; Cell Culture Techniques; Cells; Cessation of life; Citrulline; Complement; Data; Dependence; Development; Disease; Free Radicals; Genus Mycobacterium; Goals; Health; Hematopoietic; Host Defense; Host Defense Mechanism; Human; Immune; Immune Evasion; Immune response; Immune system; Immunity; Individual; Infection; Infection Control; Knowledge; Lung; Mass Spectrum Analysis; Mechanics; Mediating; Metabolism; Methods; Mission; Mus; Mycobacterium Infections; Mycobacterium tuberculosis; Myeloid Cells; NOS2A gene; National Institute of Allergy and Infectious Disease; Nitric Oxide; Nitric Oxide Synthase; Pathway interactions; Patient Care; Patients; Pharmaceutical Preparations; Production; Public Health; Publishing; Reporting; Research; Resistance; Resistance development; Role; Source; Supplementation; Testing; Therapeutic; Time; Treatment Cost; Tuberculosis; United States National Institutes of Health; amino acid metabolism; arginase; bactericide; base; cost effective; design; experimental study; immune function; in vitro activity; in vivo; innovation; killings; macrophage; man; mutant; mycobacterial; novel; novel strategies; novel therapeutics; nutrition; pathogen; response; targeted treatment; therapeutic target; treatment strategy

PROJECT SUMMARY/ABSTRACT Current anti-tuberculosis (TB) strategies require months of treatment, and the development of multi-drug re- sistant mutants of M. tuberculosis (Mtb) has increased both the complexity and cost of treatment. As such, the NIAID recently proposed targeting infected individuals’ responses to infection as a means to enhance anti-TB defenses. These “host-directed therapies” could be combined with proven antibiotic strategies against TB, providing an overall enhancement of treatment and patient care. Amino acids are integral to immune function, yet there is a fundamental gap in understanding the therapeutic potential of targeting amino acid metabolism during disease. The long-term goal is to define the interplay between amino acid metabolism and immune re- sponses, providing new therapeutic avenues to manipulate immune activity. The objective of this study is to identify the role of L-citrulline metabolism on macrophage (MФ)-mediated immune responses to Mtb. The ap- plicant will use Mtb H37Rv infection in human and mouse MФs, as well as in vivo infection in mice, to examine L-citrulline metabolism during Mtb infection. The central hypothesis is that L-citrulline metabolism is required for anti-TB MФ activity and can be harnessed to assist host defense to TB in vivo. The hypothesis is support- ed as a) L-citrulline enhances MΦ NO production and anti-Mtb activity in vitro, b) L-citrulline metabolism by myeloid cells is necessary for mycobacterial defenses in vivo, c) L-citrulline supplementation decreases lung mycobacterial burden, and d) lung MФs are the predominant L-citrulline utilizing cells during infection. The ra- tionale for the proposed research is that uncovering mechanics of immune-mediated infection control will likely lead to novel methods for treating those infected with Mtb – which kills well over 1 million annually. The appli- cant will test the central hypothesis by investigating three specific aims: 1) to examine how L-citrulline is uti- lized in Mtb-infected MФs, 2) to define the metabolism of L-citrulline in human MΦs infected with Mtb, and 3) to identify how harnessing L-citrulline metabolism enhances anti-mycobacterial host defenses. Under the first and second aims, the applicant will utilize a combination of innovative cell culture and mass spectrometry ap- proaches with titrating amino acid concentrations to determine the benefit(s) of L-citrulline metabolism in hu- man and mouse MФs. These experiments will define the mechanistic consequences of this pathway that will complement in vivo experiments under the third aim, where the applicant will use an original approach to en- hance Mtb clearance in the lungs by supplementing mice with L-citrulline. The proposed research is significant as we anticipate harnessing L-citrulline metabolism will augment MФ-mediated control of TB, and in combina- tion with anti-mycobacterial antibiotic therapy will result in efficient treatment strategies for patients suffering with TB. This research is also expected to have broad implications on host defense mechanisms – enhancing pathogen control and individual components of the immune system by altering amino acid metabolism.

项目摘要/摘要 当前的抗结核（TB）策略需要几个月的治疗，并且多药的发展 结核分枝杆菌（MTB）的持续突变体增加了治疗的复杂性和成本。因此， NIAID最近提出针对感染个体对感染的反应，以此作为增强抗TB的一种手段 防御。这些“宿主指导的疗法”可以与针对结核病的经过验证的抗生素策略相结合， 提供治疗和患者护理的总体增强。氨基酸是免疫功能不可或缺的， 然而，了解靶向氨基酸代谢的治疗潜力存在根本的差距 疾病期间。长期目标是定义氨基酸代谢和免疫恢复之间的相互作用 发起人提供新的治疗途径来操纵免疫活动。这项研究的目的是 确定L-硫氨酸代谢对巨噬细胞（MO）介导的MTB免疫反应的作用。 ap- Plicant将在人和小鼠MOS以及小鼠的体内感染中使用MTB H37RV感染来检查 MTB感染期间的L-核酸代谢。中心假设是需要L-策曲氨酸代谢 对于抗TB MO活性，可以利用用于在体内对TB的托管防御。该假设是支持 - ED作为A）L-硫氨酸在体外增强了Mφ无产生和抗MTB活性，b）l-citrulline代谢 髓样细胞对于体内的分枝杆菌防御必不可少 分枝杆菌伯嫩和d）肺MOS是在感染过程中利用细胞的主要L-核酸。 ra- 拟议研究的tionale是，发现免疫介导的感染控制机制可能会 导致新的方法来治疗感染MTB的人 - 每年造成超过100万的杀死。应用 不能通过研究三个特定目的来检验中心假设：1）检查l-citrulline如何取代 在MTB感染的MOS中liz，2）定义了在感染MTB的人Mφ中L-citrulline的代谢，3）to 确定利用L-策曲氨酸代谢如何增强抗菌宿主防御能力。在第一个 第二目的是，申请人将利用创新的细胞培养和质谱法的结合 滴定氨基酸浓度的批准，以确定L-策曲氨酸代谢的益处 男子和鼠标MOS。这些实验将定义该途径的机械后果 补充第三个目标下的体内实验，申请人将使用原始方法来实现 通过补充L-硫氨酸的小鼠，Hance MTB清除肺中的清除率。拟议的研究很重要 正如我们预计利用L-硫氨酸的代谢将增强MO介导的TB的控制，并以组合的控制 抗菌抗生素疗法的影响将为患者带来有效的治疗策略 与结核病。预计这项研究将对宿主防御机制产生广泛的影响 - 增强 通过改变氨基酸代谢，病原体控制和免疫系统的单个成分。