Tfh dysfunction in HIV and Aging

HIV 和衰老中的 Tfh 功能障碍

基本信息

批准号：
10425451
负责人：
SURESH PALLIKKUTH
金额：
$ 75.25万
依托单位：
UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-30 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10425451
关键词：
AIDS/HIV problem Address Affect Age Aging Antibodies Antibody Affinity Antibody Response Antigens Autologous B-Lymphocytes Binding Biological Assay CD4 Positive T Lymphocytes Cell Communication Cell physiology Cells Characteristics Classification Clonal Expansion Coculture Techniques Coupled Data Set Defect Development Diabetic Ketoacidosis Disease Dose Effectiveness Elderly Evaluation Failure Feasibility Studies Florida Flow Cytometry Functional disorder General Population Generations HIV HIV Infections HIV Seronegativity Ha antigen Helper-Inducer T-Lymphocyte Home Immune Immune response Immune system Immunity Immunocompetence Impairment In Vitro Incidence Individual Inflammaging Inflammation Inflammatory Influenza Influenza vaccination Interleukin-2 Intervention Kinetics Lead Longevity Lymphoid Tissue Memory B-Lymphocyte Monoclonal Antibodies Myocardial Infarction Participant Peripheral Persons Phenotype Phosphorylation Plant Roots Plasma Cells Population Property Reporting Resolution Risk Role Seasons Serology Signal Transduction Stat5 protein Stroke Structure of germinal center of lymph node T-Lymphocyte Subsets TNF gene TNFSF5 gene Technology Testing United States Up-Regulation Vaccination Vaccines Viral Virus antiretroviral therapy base bioinformatics resource co-infection comorbidity data integration flu human old age (65+)immune activation improved in vitro testing in vivo inflammatory marker influenza infection influenza virus vaccine insight interest monocyte novel peripheral blood programmed cell death protein 1 recruit responders and non-responders response seasonal influenza senescence single-cell RNA sequencing success vaccine response vaccine-induced antibodies

项目摘要

With effective ART, HIV infected persons can achieve a near normal life span but have increasing incidence of comorbidities and co-infections that occur earlier, are more frequent than the general population. Underlying inflammation is considered to be a major factor for comorbidities, but less well appreciated is the associated immune deficiency that persist even after durable virologic control, putting people living with HIV (PWH) at greater risk for influenza, for which flu vaccinations are recommended. Besides decreasing risk for influenza infection, flu vaccines can serve as probes for testing host immune competence an approach used in this proposal and in a previous project (AI108472) for assessing immunity in PWH and we could classify participants as vaccine responders (VR) and vaccine non-responders (VNR). We observed that aging and HIV had a negative effect on vaccine response. In studying mechanisms of immune defects in VNR, we identified quantitative and qualitative defects in peripheral T follicular helper cells (pTfh), which are a subset of CD4 T cells that are essential for vaccine-induced antibody (Ab) responses. The pTfh displayed a skewed polarization away from a favorable IL-21 secreting phenotype towards a detrimental IL-2 secreting Th1 phenotype, coupled with abundance of inflammatory markers, resulting in failure of pTfh to provide B cells with the helper signals required for Ab secretion. Our central hypothesis is that skewed polarization of pTfh away from a favorable IL-21 secreting phenotype towards one of IL-2 and inflammation is detrimental, worsens with age or HIV but is amenable to change by ex-vivo and in-vivo manipulation. We will recruit HIV negative and virally suppressed HIV+ populations to address key questions on Ab response following seasonal influenza vaccination. The project has 3 aims: Aim 1 will investigate cell-intrinsic properties of pTfh cells that influence their function in the context of age, HIV infection and the generation of memory B cells. Aim 2 will investigate VNR to define mechanism of pTfh dysfunction via study of cellular and molecular interactions affecting pTfh function and will test in-vitro interventions to reverse the pTfh dysfunction. Aim 3 will test whether administering high dose flu vaccine improves immune response in VNR from all groups and will investigate the immune mechanisms affected. In this project we will evaluate immune cell populations of interest using a combination of technologies including multi-parameter flow cytometry, single cell RNA sequencing, repertoire sequencing, monoclonal Ab generation and cell co- cultures to gain high resolution datasets. Our approach will obtain a snapshot of immune perturbation of pTfh cells in aging and HIV infection. In vitro studies with purified cell subsets will allow for mechanistic evaluation of the immune system. These studies are feasible, given our expertise in the technologies described, access to desired population and resources for bioinformatics and data integration. We expect to provide novel insights into immune perturbations that will help in strategizing vaccine approaches in aging populations.

通过有效的抗逆转录病毒治疗，艾滋病毒感染者可以达到接近正常的寿命，但发病率却在增加较早发生的合并症和合并感染比一般人群更常见。潜在的炎症被认为是合并症的一个主要因素，但不太受重视的是即使在持久的病毒学控制后，相关的免疫缺陷仍然持续存在，使艾滋病毒感染者 (PWH) 感染流感的风险较高，建议接种流感疫苗。除了降低风险流感感染，流感疫苗可以作为检测宿主免疫能力的探针，使用的方法在本提案和之前评估感染者免疫力的项目（AI108472）中，我们可以分类参与者分为疫苗反应者（VR）和疫苗非反应者（VNR）。我们观察到衰老和艾滋病毒对疫苗反应有负面影响。在研究 VNR 免疫缺陷的机制时，我们确定了外周滤泡辅助 T 细胞 (pTfh) 的定量和定性缺陷，该细胞是一个子集 CD4 T 细胞对于疫苗诱导的抗体 (Ab) 反应至关重要。 pTfh 显示偏向极化，从有利的 IL-21 分泌表型转向有害的 IL-2 分泌 Th1 表型，加上大量炎症标记物，导致 pTfh 无法提供 B 具有抗体分泌所需的辅助信号的细胞。我们的中心假设是倾斜的两极分化 pTfh远离有利的IL-21分泌表型而转向IL-2和炎症之一是有害的，随着年龄或艾滋病毒的增加而恶化，但可以通过离体和体内操作来改变。我们将招募艾滋病毒阴性和病毒抑制的 HIV+ 人群，以解决以下抗体反应的关键问题季节性流感疫苗接种。该项目有 3 个目标：目标 1 将研究 pTfh 的细胞内在特性细胞在年龄、HIV 感染和记忆 B 细胞的生成中影响其功能。目标 2 将研究 VNR，通过细胞和分子研究来定义 pTfh 功能障碍的机制影响 pTfh 功能的相互作用，并将测试体外干预措施以逆转 pTfh 功能障碍。目标 3 将测试注射高剂量流感疫苗是否可以改善所有群体的 VNR 免疫反应并将调查受影响的免疫机制。在这个项目中，我们将评估免疫细胞使用多参数流式细胞术、单细胞 RNA 测序、库测序、单克隆抗体生成和细胞共培养以获得高分辨率数据集。我们的方法将获得 pTfh 细胞在衰老和衰老过程中免疫扰动的快照。艾滋病毒感染。纯化细胞亚群的体外研究将允许对免疫机制进行评估系统。鉴于我们在所描述的技术方面的专业知识，这些研究是可行的，可以获得所需的生物信息学和数据集成的人口和资源。我们期望提供新颖的见解免疫扰动将有助于制定针对老龄化人口的疫苗方法策略。