Ablation of HIV-1 infected cells by sustained bNAb expression from B-cells

B 细胞持续表达 bNAb 消除 HIV-1 感染细胞

基本信息

批准号：
10160821
负责人：
Koki Morizono
金额：
$ 46.67万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
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：
2020-05-07 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10160821
关键词：
Ablation Animal Model Antibodies Antibody Formation Antibody-Producing Cells Antigen Presentation Applications Grants Autoantigens Autoimmune Diseases Autoimmunity B Cell Proliferation B-Cell Antigen Receptor B-Cell Receptor Binding B-Lymphocytes Biodistribution Blood Bone Marrow Cell Differentiation process Cell Proliferation Cells Cellular Immunity Chromosomes Chronic Clinical Trials Collaborations Communicable Diseases Complement Complement Activation Complement-Dependent Cytotoxicity Disease Dose Drug Kinetics Elements Factor IX Gene Transduction Agent Genes Genetic Engineering Genetic Recombination Genome Gut associated lymphoid tissue HIV HIV-1 Hemophilia A Human Humoral Immunities Immune Immunology Infection Infection prevention Inflammation Infusion procedures Intramuscular Intravenous Lentivirus Vector Longevity Lymphoid Lymphoid Tissue Malignant Neoplasms Mediating Membrane Memory B-Lymphocyte Methods Mus Muscle Mutation Physiological Plasma Cells Receptor Signaling Recombinants Safety Serum Site Structure Suicide Therapeutic Time Tissues Transgenes Viral Viremia Virus Virus Diseases Virus Replication anti-viral efficacy antibody-dependent cell cytotoxicity base cell type cellular transduction complement system cost cytotoxicity design engineered T cells experimental study gene therapy hematopoietic tissue humanized mouse immunoreaction in vivo inhibitor/antagonist lentiviral-mediated lymph nodes mouse model neutralizing antibody nonhuman primate novel therapeutic gene transgene expression vector

项目摘要

Project 2: Summary/Abstract Broadly neutralizing antibodies (bNAbs) against HIV-1 can inhibit viral replication by two distinct mechanisms. One is the neutralization of virus, which prevents infection. The other is its ability to kill HIV-1 infected cells through activation of complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC). Thus, bNAbs have the potential to not only inhibit new viral infection cycles but also eliminate chronically infected cells, which are necessary for cure of the HIV-1 disease. However, the serum concentrations of the antibodies must be kept at therapeutic levels for long periods of time to eliminate HIV-1-infected cells, because persistently infected cells reside in the deep tissue. Therefore, multiple administrations of the antibodies are required, which could be expensive and labor-intensive. In addition, administration of recombinant bNAbs can raise host immune reactions to the bNAbs, leading to loss of neutralization and cytotoxicity activities of bNAbs and shortening their halflife. Gene therapy vectors, especially lentiviral/oncoretroviral vectors that integrate their transgene into host chromosomes, can produce bNAbs in vivo for long periods. But immune reactions against the bNAbs can still decrease the antiviral efficacy of bNAbs and shorten the duration of bNAb expression. B cells physiologically express wide varieties of valuable antibody regions generated by recombination and mutations in genes. B cells are known to induce tolerance to the valuable regions. This ability of B cells was previously used to induce tolerance to self-antigens for therapy of autoimmune diseases and coagulation factor IX for treatment of hemophilia. Therefore, transduction of B cells with bNAb expressing vectors is likely to generate long-term bNAbs without inducing immune reactions to the bNAbs. We have developed lentiviral vectors that can specifically transduce desired target cell types after systemic administration. By specific transduction of B cells by this lentiviral vector, we will attempt to express bNAbs for long periods of time by avoiding immune reactions against bNAbs. We will also attempt to prolong the duration of bNAb expression by differentiating transduced B-cells to long-lived plasma cells and memory B-cells, which have long life-span. We will then investigate if bNAbs expressed from B-cells can eliminate HIV-1-infected cells in mice. Since commonly used mice do not have normal complement, we will use a novel type of mouse model that has an intact complement system for full CDC activity of the bNAb. We will next investigate whether bNAbs expressed from B cells and T cells engineered to express anti-HIV-1 transgene can synergistically eliminate HIV-1 infected cells in the B cells. Lastly, we will investigate whether systemic administration of our B-cell targeting lentiviral vector can specifically transduce B cells in non-human primates (NHP) by analyzing biodistribution and cell types of transduced cells. We will also investigate the pharmacokinetics of and immune reactions to bNAbs expressed in NHP. These experiments are designed to develop a novel bNAb-based gene therapeutic approach, which can be applicable to other infectious diseases.

项目 2：总结/摘要针对 HIV-1 的广泛中和抗体 (bNAb) 可以通过两种不同的机制抑制病毒复制。一是中和病毒，防止感染。另一个是它通过激活补体依赖性细胞毒性（CDC）和抗体依赖性细胞毒性（ADCC）来杀死 HIV-1 感染细胞的能力。因此，bNAb 不仅有可能抑制新的病毒感染周期，还可以消除慢性感染细胞，这是治愈 HIV-1 疾病所必需的。然而，抗体的血清浓度必须长时间保持在治疗水平，以消除HIV-1感染的细胞，因为持续感染的细胞驻留在深层组织中。因此，需要多次施用抗体，这可能是昂贵且劳动密集型的。此外，重组bNAb的施用可以提高宿主对bNAb的免疫反应，导致bNAb中和和细胞毒性活性的丧失并缩短其半衰期。基因治疗载体，尤其是将转基因整合到宿主染色体中的慢病毒/肿瘤逆转录病毒载体，可以在体内长时间产生bNAb。但针对 bNAb 的免疫反应仍会降低 bNAb 的抗病毒功效并缩短 bNAb 表达的持续时间。 B 细胞在生理上表达多种由基因重组和突变产生的有价值的抗体区域。已知 B 细胞会诱导对有价值区域的耐受性。 B细胞的这种能力以前被用来诱导对自身抗原的耐受性以治疗自身免疫性疾病，并诱导对凝血因子IX的耐受性以治疗血友病。因此，用 bNAb 表达载体转导 B 细胞可能会产生长期的 bNAb，而不诱导对 bNAb 的免疫反应。我们开发了慢病毒载体，可以在全身给药后特异性转导所需的靶细胞类型。通过用这种慢病毒载体特异性转导 B 细胞，我们将尝试通过避免针对 bNAb 的免疫反应来长时间表达 bNAb。我们还将尝试通过将转导的 B 细胞分化为寿命较长的长寿命浆细胞和记忆 B 细胞来延长 bNAb 表达的持续时间。然后我们将研究 B 细胞表达的 bNAb 是否可以消除小鼠体内 HIV-1 感染的细胞。由于常用的小鼠没有正常的补体，我们将使用一种新型的小鼠模型，该模型具有完整的补体系统，可实现 bNAb 的完整 CDC 活性。接下来我们将研究 B 细胞和 T 细胞表达的 bNAb 是否可以协同消除 B 细胞中 HIV-1 感染的细胞。最后，我们将通过分析转导细胞的生物分布和细胞类型来研究全身施用我们的 B 细胞靶向慢病毒载体是否可以特异性转导非人灵长类动物 (NHP) 中的 B 细胞。我们还将研究 NHP 中表达的 bNAb 的药代动力学和免疫反应。这些实验旨在开发一种基于 bNAb 的新型基因治疗方法，可适用于其他传染病。