CTL mechanisms underlying effects of HLA-A*2301 and B*5301 on HIV-1 set-point

HLA-A*2301 和 B*5301 对 HIV-1 设定点影响的 CTL 机制

• 批准号: 9067915
• 负责人: ROMEL D MACKELPRANG
• 金额: $ 12.83万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-15 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9067915
• 关键词: Advisory Committees; Affect; Affinity; Africa South of the Sahara; African; Alleles; Allogenic; Antigens; Basic Science; Binding; Biological Assay; Biometry; CD8B1 gene; Caucasians; Cell Maturation; Cell Proliferation; Cells; Characteristics; Child; Clinic; Clinical Research; Couples; Cytotoxic T-Lymphocytes; Data; Data Analyses; Dendritic Cells; Development; Disease Progression; Doctor of Philosophy; Effectiveness; Epidemiology; Epitopes; Evaluation; Fathers; Feedback; Flow Cytometry; Funding; Genetic; Genomics; Granzyme; HIV Vaccine Trials Network; HIV vaccine; HIV-1; HIV-1 vaccine; HLA Antigens; Health; Heterogeneity; Immune; Immune Tolerance; Immune response; Immunodominant Epitopes; Immunoglobulins; Immunologic Factors; Immunology; In Vitro; Individual; Infant; Infection; Interferon Type II; Interleukin-2; International; Laboratories; Lead; Measures; Mediating; Medicine; Mentored Research Scientist Development Award; Mentors; Microbiology; Modeling; Molecular Biology; Mutation; Myelogenous; Nature; Needle-Exchange Programs; Outcome; Pathway interactions; Peptides; Perinatal; Peripheral Blood Mononuclear Cell; Plasma; Play; Population; Positioning Attribute; Postdoctoral Fellow; Predisposition; Prevalence; Production; Property; RNA; Regulation; Research; Research Training; Role; Running; Sampling; Science; Staining method; Stains; T cell response; T-Cell Proliferation; T-Lymphocyte; T-Lymphocyte Epitopes; TNF gene; TNFSF5 gene; Therapeutic Intervention; Time; Training Programs; Transcript; Universities; Vaccine Design; Vaccines; Viral Load result; Virus; Washington; Woman; Work; antigen binding; base; career; cohort; cytokine; cytotoxic; data management; experience; faculty research; fitness; functional disability; genetic association; genetic epidemiology; global health; innovation; interdisciplinary approach; interest; killer immunoglobulin-like receptor; macrophage; meetings; member; monocyte; novel; novel therapeutics; pandemic disease; perforin; prevent; professor; programs; protective effect; receptor; receptor binding; research study; response; symposium; transmission process; volunteer

DESCRIPTION (provided by applicant): My interest in HIV-1 began as a child when I volunteered at needle-exchange clinic run by my father. This interest carried forward to my doctoral studies in which I earned a PhD in epidemiology with an emphasis on genetic epidemiology of HIV-1. Since then, I have continued to research the role that host genomic factors play in HIV-1 infection as a Senior Fellow with the International Clinical Research Center at the University of Washington (UW). During both my pre and post-doctoral research, I evaluated the impact of human leukocyte antigen (HLA) class I alleles on multiple HIV-1 outcomes and found several consistent results that I build upon for this K01 Mentored Research Scientist Development Award proposal. First, in a Kenyan perinatal HIV-1 transmission cohort, women who had the A*23 allele had 0.4 log10 copies/mL higher plasma HIV-1 RNA levels and were nearly 3-times as likely to transmit HIV-1 to their infants. Second, among HIV-1 infected individuals from seroidiscordant couples, A*23 was also associated with 0.4 log10 copies/mL higher HIV-1 set-points and B*53 was associated with 0.7 higher set-points. Epidemiologic evidence suggesting that A*23 has a harmful effect during HIV-1 infection is further supported by eight other studies showing that this allele is associated with worse control of HIV-1. However, mechanisms to explain why the A*23 allele is associated with these deleterious outcomes are unknown. Previous studies have demonstrated that certain HLA alleles such as HLA-B*27 and B*57 protect against HIV-1 disease progression by restricting specific CD8+ T-cell epitopes that elicit immune responses of higher magnitude and functionality; mechanisms to explain effects of other alleles on HIV-1 are not yet understood. One hypothesis to explain associations of HLA-A*23 and B*53 with increased HIV-1 set-point is that the harmful effects are elicited in a T-cell epitope dependent manner that results in inefficient cytotoxic T-lymphocyte (CTL) responses in response to HIV-1 infection. To evaluate this hypothesis, we propose to 1) use IFN-γ ELISpot assays to determine if CTL responses to specific T-cell epitopes presented by A*23 or B*53 are associated with changes in set-point; and 2) compare qualitative differences in T-cell responses restricted by harmful and protective HLA alleles using intracellular cytokine staining and flow cytometry. Understanding why A*23 is associated with worse control of HIV-1 may help identify immunogens that hinder effectiveness of T-cell based vaccines and may further elucidate functional characteristics that differentiate protective from ineffective CTL. Alternatively, studis have increasingly demonstrated that HLA alleles can also influence immune responsiveness through alternative mechanisms such as binding to to the immunoglobulin-like transcript 4 (ILT4) receptor on dendritic cells (DC). HLA binding to ILT4 can alter DC maturation and development of tolerogenic T-cell responses. Thus, it is possible that the A*23 and B*53 alleles lead to worse control of HIV-1 by binding the ILT4 receptor more strongly than other alleles. Evaluating whether HLA-A*23 and B*53 associate with higher HIV-1 set-point levels via CTL or ILT4 mechanisms is an innovative way to constrast mechanisms for protective and harmful HLA alleles and may elucidate natural pathways leading to protection that could be used in vaccines or therapeutic interventions. Due to the interdisciplinary nature of the research objectives, I have assembled a mentoring team with considerable expertise in HIV-1 epidemiology and global health and HIV-1 immunology. Dr. Jairam Lingappa (Medicine and Global Health, UW) will serve as the primary mentor and will provide daily guidance regarding all aspects of the research and training plan with particular focus on project coordination, data interpretation, and professional development. Dr. Nicole Frahm (Associate Director for Laboratory Science at the HIV Vaccine Trials Network and Assistant Professor of Global Health, UW) will provide mentoring regarding pathobiology and immunology, and will provide laboratory space for conducting assays and experiments. As suggested by the reviewers, I have also assembled an Advisory Committee to provide evaluation and feedback regarding career progression. The Advisory Committee includes Drs. Connie Celum (Professor of Global Health, Medicine, and Epidemiology), Jim Mullins (Professor of Microbiology and Medicine), Julie McElrath (Director, HIV Vaccine Trials Network Laboratory Program) and Peter Gilbert (Co-Director of the Statistical Data Management Center of the HIV Vaccine Trials Network and Research Professor of Biostatistics). In addition to specific mentoring, I will also complete formal coursework covering HIV-1 molecular biology and will participate in conferences and other meetings where I will present my research. Overall, this research and training program will combine my expertise in epidemiology and biostatistics with new experiences working directly with basic science data, positioning me to make useful contributions to HIV- 1 research by applying interdisciplinary approaches and fulfill my short and long-term career objectives of obtaining independent R01 funding and becoming an interdisplinary research faculty member.

描述（由申请人提供）：我对 HIV-1 的兴趣始于孩童时期，当时我在父亲经营的针头交换诊所做志愿者。这种兴趣延续到了我的博士研究中，我获得了流行病学博士学位，重点是 HIV-1 的遗传流行病学。从那时起，我作为华盛顿大学 (UW) 国际临床研究中心的高级研究员，继续研究宿主基因组因素在 HIV-1 感染中的作用。在我的博士前和博士后研究期间，我评估了人类白细胞抗原 (HLA) I 类等位基因对多种 HIV-1 结果的影响，并发现了几个一致的结果，我将这些结果作为 K01 指导研究科学家发展奖提案的基础。首先，在肯尼亚围产期 HIV-1 传播队列中，携带 A*23 等位基因的女性血浆 HIV-1 RNA 水平高出 0.4 log10 拷贝/mL，并且将 HIV-1 传播给婴儿的可能性几乎是其他女性的 3 倍。其次，在来自血清不一致夫妇的 HIV-1 感染个体中，A*23 还与 0.4 log10 拷贝/mL 较高的 HIV-1 设定点相关，而 B*53 与 0.7 较高的设定点相关。流行病学证据表明 A*23 在 HIV-1 感染期间具有有害影响，这得到了其他八项研究的进一步支持，这些研究表明该等位基因与 HIV-1 控制较差有关。然而，解释 A*23 等位基因为何与这些有害结果相关的机制尚不清楚。 先前的研究表明，某些 HLA 等位基因（例如 HLA-B*27 和 B*57）通过限制特定的 CD8+ T 细胞表位来防止 HIV-1 疾病进展，这些表位可引发更高强度和功能性的免疫反应。解释其他等位基因对 HIV-1 影响的机制尚不清楚。解释 HLA-A*23 和 B*53 与 HIV-1 设定点增加之间关系的一种假设是，有害影响是以 T 细胞表位依赖性方式引起的，导致对 HIV-1 感染的低效细胞毒性 T 淋巴细胞 (CTL) 反应。为了评估这一假设，我们建议 1) 使用 IFN-γ ELISpot 测定来确定 CTL 对 A*23 或 B*53 呈现的特定 T 细胞表位的反应是否与设定点的变化相关； 2) 使用细胞内细胞因子染色和流式细胞术比较受有害和保护性 HLA 等位基因限制的 T 细胞反应的定性差异。了解为什么 A*23 与 HIV-1 控制较差相关，可能有助于识别阻碍 T 细胞疫苗有效性的免疫原，并可能进一步阐明区分保护性 CTL 和无效 CTL 的功能特征。另外，越来越多的研究表明，HLA 等位基因还可以通过其他机制影响免疫反应，例如与树突状细胞 (DC) 上的免疫球蛋白样转录物 4 (ILT4) 受体结合。 HLA 与 ILT4 的结合可以改变 DC 的成熟和耐受性 T 细胞反应的发展。因此，A*23 和 B*53 等位基因可能比其他等位基因更强烈地结合 ILT4 受体，从而导致对 HIV-1 的控制更差。评估 HLA-A*23 和 B*53 是否通过 CTL 或 ILT4 机制与较高的 HIV-1 设定点水平相关，是一种对比保护性和有害 HLA 等位基因机制的创新方法，并可能阐明导致可用于疫苗或治疗干预的保护的自然途径。 由于研究目标的跨学科性质，我组建了一支在 HIV-1 流行病学、全球健康和 HIV-1 免疫学方面拥有丰富专业知识的指导团队。 Jairam Lingappa 博士（华盛顿大学医学与全球健康）将担任主要导师，并就研究和培训计划的各个方面提供日常指导，特别关注项目协调、数据解释和专业发展。 Nicole Frahm 博士（HIV 疫苗试验网络实验室科学副主任兼威斯康星大学全球健康助理教授）将提供病理学和免疫学方面的指导，并将提供用于进行分析和实验的实验室空间。根据评审员的建议，我还组建了一个咨询委员会，提供有关职业发展的评估和反馈。咨询委员会包括博士。 Connie Celum（全球健康、医学和流行病学教授）、Jim Mullins（微生物学和医学教授）、Julie McElrath（HIV 疫苗试验网络实验室项目主任）和 Peter Gilbert（HIV 疫苗试验网络统计数据管理中心联席主任兼生物统计学研究教授）。除了具体的指导之外，我还将完成涵盖 HIV-1 分子生物学的正式课程，并将参加会议和其他会议，在这些会议上我将展示我的研究成果。总的来说，这个研究和培训项目将把我在流行病学和生物统计学方面的专业知识与直接处理基础科学数据的新经验结合起来，使我能够通过应用跨学科方法为 HIV-1 研究做出有益的贡献，并实现我获得独立 R01 资助和成为一名跨学科研究教员的短期和长期职业目标。