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

• 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
• 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

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.

项目摘要 对HIV-1的中和抗体在抑制HIV-1复制方面非常有效。但是，血清 抗体的浓度必须长时间保持治疗水平，以消除 HIV-1感染的细胞，因为被感染的细胞持续存在于深层组织中。因此，多个 需要对抗体的管理，这可能是昂贵且劳动密集型的。基因疗法 向量可用于产生治疗性抗体。但是，通过任何基因治疗的转基因表达 包括慢病毒载体在内的载体可以诱导针对转基因的免疫反应，从而减少 转基因产物的治疗作用并消除转导的细胞。因此，重要的是 在细胞类型中的表达转基因，可以发展出对转基因产物的耐受性。 B细胞在生理上 由基因重组和突变产生的多种有价值的抗体区域的广泛多种。 B细胞 已知会引起对宝贵地区的宽容。 B细胞的这种能力先前用于诱导 对自身免疫性疾病治疗的自我抗原的耐受性和凝结因子IX治疗 血友病。因此，B细胞的转导可能会产生长期的抗HIV-1抗体 诱导对抗体的免疫反应。我们已经开发了慢病毒载体 全身给药后传递所需的靶细胞类型。矢量可以选择性地传递脾 B细胞无靶向B细胞靶向的配体。通过利用我们的B细胞特异性转导 慢病毒载体，我们将尝试在B细胞中专门表达抗HIV-1蛋白，以增强对耐受性的耐受性 转基因产品。通过 将其与B细胞特异性启动子的转录B细胞靶向相结合。使用此高度B细胞特异性 转基因表达系统，我们将表达ECD4-Ig，这是一种由IgG和 可溶性CD4，在免疫能力的小鼠中。我们将研究ECD4-ig表达是否特别是在B细胞中 可以通过诱导发展耐受性来诱导ECD4-Ig的长期表达。接下来我们将表达两者 B细胞中的分泌和膜锚定形式的ECD4-Ig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是否引起与HIV-1包膜蛋白结合后的信号， 诱导转导细胞的分化和生长。转导的B细胞的增长将增加 ECD4-Ig的血清浓度。转导细胞与记忆B细胞和浆细胞的分化将 通过延长转导B细胞的寿命来扩展ECD4-Ig表达的周期。然后我们将评估 B细胞特异性表达ECD4-Ig在人源化BLT小鼠的HIV-1感染中的治疗作用。这些 实验旨在开发一种新型的基因治疗抗体，不仅可以应用于治疗 HIV-1感染，以及其他类型的传染病。