T CELL SUBSETS AND THEIR FUNCTION IN TB/HIV PARADOXICAL REACTIONS

T 细胞亚群及其在 TB/HIV 矛盾反应中的功能

• 批准号: 7554709
• 负责人: ANNE GOLDFELD
• 金额: $ 36.75万
• 依托单位: IMMUNE DISEASE INSTITUTE, INC.
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7554709
• 关键词: Acquired Immunodeficiency Syndrome; Africa; Antibody Formation; Antigens; Antitubercular Agents; Asia; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; CD8B1 gene; Cambodia; Cause of Death; Cell Count; Cell physiology; Clinical; Clinical Trials; Clinical Trials Design; Development; Disease; Enzyme-Linked Immunosorbent Assay; Goals; HIV; HIV Antigens; HIV-1; Highly Active Antiretroviral Therapy; Immune; Immune response; Immunosuppressive Agents; In Vitro; Individual; Infection; Inflammatory; Laboratory Markers; Lead; Life; Mediating; Memory; Methods; Mycobacterium tuberculosis; Patients; Peripheral Blood Mononuclear Cell; Pharmacotherapy; Phase; Phenotype; Plasma; Production; Protocols documentation; Reaction; Risk; Role; Staining method; Stains; Stimulus; Symptoms; Syndrome; T-Cell Proliferation; T-Lymphocyte; T-Lymphocyte Subsets; Testing; Time; Tuberculin; Tuberculosis; United States National Institutes of Health; Viral Load result; acronyms; antiretroviral therapy; base; cytokine; design; immunosuppressed; improved; insight; memory CD4 T lymphocyte; mortality; novel marker; novel therapeutic intervention; pathogen; peripheral blood; public health relevance; reconstitution; research study; response; restoration; treatment strategy; tuberculosis treatment

DESCRIPTION (provided by applicant): Tuberculosis (TB) is the leading cause of death in AIDS patients worldwide. Although the use of highly active antiretroviral therapy (HAART) during TB treatment in HIV-1/Mycobaterium tuberculosis (MTb) co-infected patients is associated with reduced mortality, it can also result in life threatening "paradoxical reactions" (PR), which occur in 7-36% of co-infected patients treated for both diseases. PR occurs after initial clinical TB improvement and within approximately 4-6 weeks after HAART initiation. Very little is known about the origin and mechanisms behind PR, except that it is associated with increased CD4+ T cell counts and the exacerbation of tuberculin-specific Th1 responses in peripheral blood. Our hypothesis, to be tested in this proposal, is that the mechanism underlying PR in HIV-1/TB co-infection occurs due to an unbalanced reconstitution of immune effector responses resulting in exaggerated CD4+ {and CD8+}T lymphocyte activities to MTb antigens. We hypothesize that these exaggerated T cell responses develop in PR+ patients, but not in PR- patients, due to a more robust rise of MTb-specific T cells and/or decreased reconstitution of immunosuppressive regulatory T cells (Tregs) within the CD4+ T cell compartment. Here, we propose to test this hypothesis by investigating peripheral blood CD4+ (memory, naive, Tregs) and {CD8+ (memory, naive)} T cell subsets and their function in immunosuppressed TB/AIDS patients on dual therapy from an ongoing clinical trial in Cambodia. This trial, called CAMELIA (CAMbodian Early vs. Late Introduction of Antiretrovirals), is designed to determine the optimal timing of HAART initiation in co-infected AIDS patients on TB therapy. {Nesting these studies in the CAMELIA gives us a unique time-limited opportunity} to (i) define the immunological mechanisms underlying PR; (ii) define the mechanisms of reconstitution of T cell functions in TB/HIV-1 co-infection; and (iii) to associate these T cell responses with clinical and laboratory markers found in PR patients in the CAMELIA trial.} To accomplish these goals, we will prospectively analyze CD4+ and CD8+ T cell subsets and their proliferative capacity and cytokine responses using several methods, including intracellular cytokine staining (ICS), proliferation analysis and ELISA, in response to a number of MTb and HIV- 1-specific stimuli. We also hypothesize that we will identify specific anti-TB antibody responses in PR+ patients by comparing responses prior to and after HAART initiation, as well as during PR. We anticipate that these studies will elucidate the origin and mechanisms underlying PR, and will identify key features of CD4+ {and CD8+ } T cell restoration during HAART and TB therapy. We also expect that we will identify markers and new anti-TB antibody responses that are predictive of the emergence of PR. Finally, we anticipate that these studies will give us fundamental insights into the immune response to TB and HIV-1 and, thus, to new therapeutic approaches to TB and AIDS co-infection. PUBLIC HEALTH RELEVANCE: Tuberculosis (TB) is the largest cause of death in the setting of AIDS, particularly in Asia and Africa, and has claimed an estimated one third to one half of the 30 million people who have from AIDS-related causes to date. Unfortunately, simultaneous treatment of the two diseases is complicated by a phenomenon known as the `paradoxical reaction' where the patient deteriorates with symptoms of progressive TB after symptoms had improved on drug therapy. Intriguingly, the paradoxical reaction appears to be an immune-mediated phenomenon since both the TB and HIV-1 infections are responding to therapy when it occurs. Thus, the paradoxical reaction provides a unique opportunity to study exaggerated immune responses to TB and AIDS and, by doing so, to gain a fundamental understanding into the basic immune response to both pathogens. In addition, another goal of this proposal is to better understand the basic immune response involved in the paradoxical reaction so that we may be better able to predict who may be susceptible to it, as well as devise better treatment strategies for when it occurs. We will conduct these studies in the context of an ongoing clinical trial designed to determine the optimal timing of TB and AIDS co-therapy in Cambodia.

描述（由申请人提供）：结核病（TB）是全球艾滋病患者死亡的主要原因。虽然在艾滋病毒-1/结核分枝杆菌（MTb）合并感染患者的结核病治疗期间使用高活性抗逆转录病毒疗法（HAART）与降低死亡率有关，但它也可能导致危及生命的“矛盾反应”（PR），在接受两种疾病治疗的合并感染患者中，7-36%发生了这种反应。PR发生在结核病最初临床改善后和HAART治疗开始后约4-6周内。关于PR的起源和机制知之甚少，除了它与外周血中CD4+ T细胞计数增加和结核菌素特异性Th1反应加剧有关。我们的假设是，HIV-1/TB合并感染中PR的机制是由于免疫效应反应的不平衡重建导致CD4+{和CD8+}T淋巴细胞对MTb抗原的活性夸大而发生的。我们假设这些夸大的T细胞反应在PR+患者中发生，而在PR-患者中则没有，这是由于CD4+ T细胞室中mtb特异性T细胞的更强劲上升和/或免疫抑制调节性T细胞（Tregs）的重构减少。在这里，我们建议通过研究柬埔寨正在进行的一项临床试验中免疫抑制的结核病/艾滋病患者的外周血CD4+（记忆，幼稚，Tregs）和{CD8+（记忆，幼稚）}T细胞亚群及其功能来验证这一假设。这项名为CAMELIA（柬埔寨早期与晚期引入抗逆转录病毒药物）的试验旨在确定在接受结核病治疗的合并感染艾滋病患者中启动HAART的最佳时机。{在CAMELIA中进行这些研究为我们提供了一个独特的时间有限的机会}来(i)定义PR背后的免疫机制；（ii）确定结核/HIV-1合并感染中T细胞功能重构的机制；（iii）将这些T细胞反应与CAMELIA试验中PR患者中发现的临床和实验室标记物联系起来。为了实现这些目标，我们将使用多种方法，包括细胞内细胞因子染色（ICS），增殖分析和ELISA，前瞻性地分析CD4+和CD8+ T细胞亚群及其增殖能力和细胞因子反应，以响应许多MTb和HIV- 1特异性刺激。我们还假设，通过比较HAART启动前后和PR期间的反应，我们将确定PR+患者的特异性抗结核抗体反应。我们预计这些研究将阐明PR的起源和机制，并将确定在HAART和结核病治疗期间CD4+{和CD8+} T细胞恢复的关键特征。我们还期望我们将识别出预测PR出现的标记物和新的抗结核抗体反应。最后，我们预计这些研究将为我们提供对结核病和HIV-1的免疫反应的基本见解，从而为结核病和艾滋病合并感染提供新的治疗方法。