B-cell-specific transduction for anti-HIV antibody and B-cell receptor expression

用于抗 HIV 抗体和 B 细胞受体表达的 B 细胞特异性转导

基本信息

批准号：
9753437
负责人：
Koki Morizono
金额：
$ 39万
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：
2019
资助国家：
美国
起止时间：
2019-02-15 至 2024-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9753437
关键词：
Amino Acid Sequence Animal Model Antibodies Antibody Formation Antibody Therapy Applications Grants Autoantigens Autoimmune Diseases B cell differentiation B-Cell Development B-Cell Receptor Binding B-Lymphocytes BLT mice Binding Cells Chromosomes Communicable Diseases Development Differentiation and Growth Factor IX Fc domain Gene Transduction Agent Genes Genetic Recombination Genetic Transcription Growth HIV Antibodies HIV therapy HIV-1 Hemophilia A Human Immune Immune response Immunocompetent Immunoglobulin G Immunoglobulin Variable Region Infection Intravenous Lentivirus Vector Ligands Longevity Membrane Memory B-Lymphocyte Methods Mus Mutation Pathology Physiological Plasma Cells Positioning Attribute Proliferating Proteins Public Health Reagent Receptors, Antigen, B-Cell Research Serum Signal Transduction Specificity Structure System Therapeutic Therapeutic Effect Therapeutic antibodies Time Tissues To autoantigen Transgenes Treatment Efficacy Viral Proteins Viral Vector Virus Virus Replication base cell growth cell type cellular transduction cost design differentiated B cell env Gene Products experimental study gene therapy immunoreaction in vivo in vivo imaging inhibitor/antagonist mouse model neutralizing antibody novel promoter receptor expression therapeutic gene tool transgene expression vector

项目摘要

PROJECT SUMMARY Neutralizing antibodies against HIV-1 are very potent in suppressing HIV-1 replication. 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. Gene therapy vectors can be used to produce therapeutic antibodies. However, transgene expression by any gene therapy vectors, including lentiviral vectors, can induce immune reactions against the transgenes, thereby decreasing the therapeutic effects of transgene products and eliminating the transduced cells. Therefore, it is important to express transgenes in the cell types that can develop tolerance to transgene products. 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 is likely to generate long-term anti-HIV-1 antibodies without inducing immune reactions to the antibodies. We have developed lentiviral vectors that can specifically transduce desired target cell types after systemic administration. The vector can selectively transduces splenic B-cells without conjugation of any B-cell-targeting ligand. By exploiting this B-cell-specific transduction by our lentiviral vectors, we will attempt to express anti-HIV-1 proteins specifically in B-cells to develop tolerance to the transgene products. We will further increase specificity of transgene expression with our targeting vector by combining it with transcriptional B-cell targeting by a B-cell-specific promoter. Using this highly B-cell-specific transgene expression system, we will express eCD4-Ig, a highly potent anti-HIV-1 reagent consisting of IgG and soluble CD4, in immunocompetent mice. We will investigate whether eCD4-Ig expression, specifically in B-cells, can induce long-term expression of eCD4-Ig by inducing developing tolerance. We will next express both secretory and membrane-anchored forms of eCD4-Ig in B-cells to generate an anti-HIV-1 B-cell receptor (BCR) on B-cells. We will investigate whether anti-HIV-1 BCR elicits signals upon binding to the HIV-1 envelope protein, inducing differentiation and growth of the transduced cells. The growth of transduced B-cells will increase the serum concentrations of eCD4-Ig. Differentiation of transduced cells to memory B-cells and plasma cells will extend the period of eCD4-Ig expression by prolonging the life span of transduced B-cells. We will then evaluate the therapeutic effects of B-cell-specific expression of eCD4-Ig in HIV-1 infection of humanized BLT mice. These experiments are designed to develop a novel gene therapeutic antibody that can be applied not only to therapy of HIV-1 infection, but also other types of infectious diseases.

项目概要 HIV-1 中和抗体能够非常有效地抑制 HIV-1 复制。然而，血清抗体浓度必须长期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，多需要施用抗体，这可能是昂贵且劳动密集型的。基因治疗载体可用于产生治疗性抗体。然而，任何基因疗法的转基因表达载体，包括慢病毒载体，可以诱导针对转基因的免疫反应，从而减少转基因产品的治疗效果和消除转导的细胞。因此，重要的是在可以对转基因产品产生耐受性的细胞类型中表达转基因。 B细胞生理学表达由基因重组和突变产生的多种有价值的抗体区域。 B细胞已知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用于治疗自身免疫性疾病，对凝血因子 IX 的耐受性用于治疗血友病。因此，B细胞的转导很可能会产生长期的抗HIV-1抗体，而无需诱导针对抗体的免疫反应。我们开发了慢病毒载体，可以特异性地全身给药后转导所需的靶细胞类型。该载体可以选择性转导脾脏未结合任何 B 细胞靶向配体的 B 细胞。通过我们的研究人员利用这种 B 细胞特异性转导慢病毒载体，我们将尝试在 B 细胞中特异性表达抗 HIV-1 蛋白，以培养对慢病毒载体的耐受性转基因产品。我们将通过我们的靶向载体进一步提高转基因表达的特异性将其与 B 细胞特异性启动子的转录 B 细胞靶向相结合。利用这种高度 B 细胞特异性转基因表达系统，我们将表达 eCD4-Ig，一种高效抗 HIV-1 试剂，由 IgG 和可溶性 CD4，在免疫功能正常的小鼠中。我们将研究 eCD4-Ig 表达（特别是在 B 细胞中）是否可以通过诱导耐受性的产生来诱导 eCD4-Ig 的长期表达。接下来我们将表达两者 B 细胞中分泌型和膜锚定型的 eCD4-Ig 可产生抗 HIV-1 B 细胞受体 (BCR) 在 B 细胞上。我们将研究抗 HIV-1 BCR 是否在与 HIV-1 包膜蛋白结合后引发信号，诱导转导细胞的分化和生长。转导的 B 细胞的生长会增加 eCD4-Ig 的血清浓度。转导细胞分化为记忆 B 细胞和浆细胞通过延长转导的 B 细胞的寿命来延长 eCD4-Ig 表达的时间。然后我们将评估 eCD4-Ig B 细胞特异性表达对人源化 BLT 小鼠 HIV-1 感染的治疗作用。这些实验旨在开发一种新型基因治疗抗体，该抗体不仅可用于治疗 HIV-1 感染，还有其他类型的传染病。