Does Antibody-Dependent Intracellular Neutralization Limit HSV-1 Reactivation?

抗体依赖性细胞内中和是否会限制 HSV-1 重新激活？

基本信息

批准号：
10573477
负责人：
David A Leib
金额：
$ 20.5万
依托单位：
DARTMOUTH COLLEGE
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-11-10 至 2024-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10573477
关键词：
Affinity Agonist Antibodies Apoptosis Bacteria Binding Blindness Brain CD8-Positive T-Lymphocytes Cell Culture Techniques Cell Lineage Cell Nucleus Cell membrane Cell surface Cells Cellular Membrane Central Nervous System Common Cold Complement Complex Cytomegalovirus Cytoplasmic Granules Cytosol Data Electroporation Equilibrium Fc Receptor Ganglia Genetic Transcription Granzyme HIV Herpes Labialis Herpes Simplex Virus Vaccines Herpesvirus 1 Human Human Herpesvirus 2 Human Herpesvirus 4 Immune Immune system Immunity Immunoglobulin A Immunoglobulin G Immunoglobulin M In Situ In Vitro Induced pluripotent stem cell derived neurons Infection Life Cycle Stages Lymphocyte Lytic Mediating Membrane Fusion MicroRNAs Modeling Molecular Monitor Mucous Membrane Nervous System Nervous System Trauma Neurons Newborn Infant Organ Peripheral Nervous System Primary Infection Production Proteins Recrudescences Repression Resistance Role Route Shelter facility Simplexvirus Structure of trigeminal ganglion Surface Testing Transcript Translating Viral Viral Antigens Viral Genome Virus Virus Latency Virus Replication Virus Shedding antiviral immunity arm cytotoxic design endosome membrane experimental study human disease human model human pathogen immunological synapse in vitro Model in vivo inhibitor interest latency associated transcript lytic gene expression mouse model multicatalytic endopeptidase complex neuron loss neurotropic pathogen perforin prevent residence seropositive stressor tau Proteins therapeutic target weapons

项目摘要

Antibodies that do not promote the destruction of pathogens in situ or prevent their internalization into target cells through opsonization are nevertheless key factors in immunity against intracellular pathogens. An important mechanism by which such “non-neutralizing” antibodies (nNAbs) curtail certain infections has been illuminated by the recent discovery of antibody-dependent intracellular neutralization (ADIN). In ADIN, cytosolic nNAbs bound to pathogens are recognized by the intracellular high-affinity Fc receptor Trim21 and the complex is degraded by the proteasome. ADIN has been found capable of eradicating an enveloped virus. Given that enveloped viruses shed bound antibodies upon cell membrane fusion, the means by which nNAbs access the cytosol is puzzling. That nNAbs access the cytosol in vivo but not in vitro suggests that culture models lack a critical cell or factor for nNAb entry. Herpes simplex viruses (HSV)-1 and -2 initially replicate in a lytic manner at mucosal surfaces but then establish life- long residence within ganglion neurons of the peripheral nervous system. In neuronal nuclei the viral genome enters latency, a state of quiescence in which replication is repressed and lytic proteins are produced at near-undetectable levels. As mature neurons are non-renewable and unchecked viral replication can lead to central nervous system damage, the control of latency is critical to the host. Ganglia are monitored by CD8+ T-cells, which deliver granzyme B at the immunological synapse with infected neurons via perforin pores. Cytosolic granzyme B digests ICP4, an essential transcriptional regulator. The model is therefore that without ICP4 to upregulate transcript production, latency is perpetuated. Our data show that ICP4 antibodies exist in seropositive human trigeminal ganglia, suggestive of a check on ICP4 expression by granzyme B and possibly by antibodies to ICP4 that mediate its ADIN. We hypothesize that antibody-dependent intracellular neutralization of ICP4 limits HSV-1 reactivation. We will address this in experiments of two Specific Aims: 1) assess whether antibodies gain access to the neuronal cytosol through the close interaction between CD8+-T-cells and latently-infected neurons; and 2) determine whether non-neutralizing antibodies direct ADIN of ICP4 produced during latent neuronal infection, stifling viral reactivation. We will use convergent approaches to benefit from both an in vivo → ex vivo mouse model of human HSV-1 latency, and an in vitro model of latent HSV-1 infection in human induced pluripotent stem cell-derived neurons. If successful, Aim 1 will define a heretofore undescribed route of nNAb entry into cells in the context of HSV-1 latency. Aim 2 will elucidate the molecular basis of the complex balance between viral latency and host immunity. If successful, this R21 study will shift the focus of HSV vaccine target design to accommodate a role for ADIN in anti-viral immunity, and indicate potential therapeutic targets including inhibitors of reactivation, or agonists of ADIN. Advances from our studies could also inform far-reaching approaches to antagonize human pathogens with a latency state including HIV, HCMV, MeV, and EBV.

不会促进原位破坏病原体或防止其内在化到靶细胞的抗体然而，通过调整是针对细胞内病原体免疫的关键因素。一个重要的机制这种“非中和”抗体（NNABS）减少某些感染的情况已被最近的感染所阐明抗体依赖性细胞内神经化（ADIN）的发现。在阿丁，与病原体结合的胞质NNAB是由细胞内高亲和力FC受体TRIM21识别，并被蛋白酶体降解。阿丁已经发现能够消除包膜病毒。鉴于包裹的病毒将结合抗体放在细胞上膜融合，NNABS进入细胞质的手段是难题。 nnabs在体内访问细胞质，但不能体外表明，培养模型缺乏关键细胞或NNAB进入的因素。单纯疱疹病毒（HSV）-1和-2最初在粘膜表面上以裂解方式复制，但随后建立生命 - 周围神经系统神经节神经元内长期居住。在神经元核中，病毒基因组进入潜伏期，一种静止的状态，其中复制受到抑制，并在接近无法探测的水平下产生裂解蛋白。由于成熟的神经元是不可再生的，并且不受检查的病毒复制会导致中枢神经系统损害，所以对延迟的控制对主机至关重要。神经节由CD8+ T细胞监测，后者在通过穿孔蛋白孔与感染神经元的免疫突触。胞质颗粒Bigests ICP4，这是必不可少的转录调节器。因此，该模型是没有ICP4上调成绩单生产的，延迟为永久。我们的数据表明，ICP4抗体存在于血清阳性人类三叉神经节中，暗示了检查颗粒酶B的ICP4表达，并通过介导其Adin的ICP4抗体可能。我们假设ICP4的抗体依赖性细胞内谈判限制了HSV-1重新激活。我们将在两个具体目的的实验中解决了这一点：1）评估抗体是否通过 CD8+-T细胞与潜在感染的神经元之间的紧密相互作用； 2）确定是否不中和在潜在神经元感染期间产生的ICP4的抗体直接adin，病毒重新激活。我们将使用转换从人体HSV-1潜伏期的体内→Ex Vivo小鼠模型中受益的方法，也是一个体外模型人类诱导多能干细胞衍生的神经元中的潜在HSV-1感染。如果成功，AIM 1将定义迄今为止，在HSV-1潜伏期的背景下，NNAB进入单元格的途径未描述。 AIM 2将阐明分子病毒潜伏期和宿主免疫之间的复杂平衡的基础。如果成功，这项R21研究将改变 HSV疫苗靶设计可容纳Adin在抗病毒免疫中的作用，并指示潜在的治疗包括重新激活抑制剂或阿丁激动剂的靶标。我们研究的进步也可能为深远的信息提供信息与艾滋病毒，HCMV，MEV和EBV在内的潜伏状态对抗人病原体的方法。