Molecular Mechanism of Immune Therapy for Bone Marrow Failures

骨髓衰竭免疫治疗的分子机制

• 批准号: 7797799
• 负责人: Pearlie K Burnette
• 金额: --
• 依托单位: JAMES A. HALEY VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7797799
• 关键词: Acute; Address; Adhesions; Adoptive Transfer; Aftercare; Age; Aging; Animal Model; Animals; Antigens; Antithymoglobulin; Aplastic Anemia; Applications Grants; Autoimmune Diseases; Autoimmune Process; Autoimmunity; Binding; Blood; Bone Marrow; Bone Marrow Cells; Bone Marrow Suppression; CD8B1 gene; Caring; Cell Adhesion Molecules; Cells; Cleaved cell; Clinical; Clinical Data; Clinical Research; Complex; Cyclophosphamide; Cyclosporine; Cytolysis; Data; Defect; Development; Diagnosis; Diagnostic; Disease; Disease Progression; Disease model; Dose; Dysmyelopoietic Syndromes; Effectiveness; Endothelial Cells; Equilibrium; Etiology; Event; Failure; Foundations; Funding; Future; Genetic Transcription; Goals; Hematopoiesis; Home environment; Homing; Immune; Immune response; Immune system; Immunosuppressive Agents; Immunotherapy; In Vitro; Incidence; Individual; Inflammatory; Integrin alpha4beta1; Integrins; L-Selectin; Laboratories; Large granular lymphocyte; Lead; Life Expectancy; Ligands; Link; Lymphocyte; Lymphocyte Homing Receptors; Lymphocytosis; Lymphoid; Manuscripts; Matrix Metalloproteinases; Mediating; Membrane; Metalloproteases; Methotrexate; Modeling; Molecular; Monitor; Mus; Myelogenous; Myelopoiesis; Pancytopenia; Pathogenesis; Pathology; Patients; Peripheral; Pharmaceutical Preparations; Pharmacotherapy; Population; Process; Production; Progress Reports; Publishing; Quality of life; Regulation; Rheumatoid Arthritis; Role; SELL gene; Spleen; Surface; Syndrome; System; T-Cell Activation; T-Cell Depletion; T-Lymphocyte; TNF-alpha converting enzyme; Testing; Theophylline; Therapeutic; Therapeutic immunosuppression; Time; Transgenic Mice; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1; Vasculitis; Veterans; Work; abstracting; alpha secretase; base; bone; chronic T-cell leukemia; cytokine; cytopenia; design; effective therapy; improved; in vivo; inhibitor/antagonist; lymph nodes; meetings; migration; mouse model; novel therapeutics; pre-clinical; preclinical study; progenitor; public health relevance; receptor; research study; trafficking; treatment strategy; Acute; Address; Adhesions; Adoptive Transfer; Aftercare; Age; Aging; Animal Model; Animals; Antigens; Antithymoglobulin; Aplastic Anemia; Applications Grants; Autoimmune Diseases; Autoimmune Process; Autoimmunity; Binding; Blood; Bone Marrow; Bone Marrow Cells; Bone Marrow Suppression; CD8B1 gene; Caring; Cell Adhesion Molecules; Cells; Cleaved cell; Clinical; Clinical Data; Clinical Research; Complex; Cyclophosphamide; Cyclosporine; Cytolysis; Data; Defect; Development; Diagnosis; Diagnostic; Disease; Disease Progression; Disease model; Dose; Dysmyelopoietic Syndromes; Effectiveness; Endothelial Cells; Equilibrium; Etiology; Event; Failure; Foundations; Funding; Future; Genetic Transcription; Goals; Hematopoiesis; Home environment; Homing; Immune; Immune response; Immune system; Immunosuppressive Agents; Immunotherapy; In Vitro; Incidence; Individual; Inflammatory; Integrin alpha4beta1; Integrins; L-Selectin; Laboratories; Large granular lymphocyte; Lead; Life Expectancy; Ligands; Link; Lymphocyte; Lymphocyte Homing Receptors; Lymphocytosis; Lymphoid; Manuscripts; Matrix Metalloproteinases; Mediating; Membrane; Metalloproteases; Methotrexate; Modeling; Molecular; Monitor; Mus; Myelogenous; Myelopoiesis; Pancytopenia; Pathogenesis; Pathology; Patients; Peripheral; Pharmaceutical Preparations; Pharmacotherapy; Population; Process; Production; Progress Reports; Publishing; Quality of life; Regulation; Rheumatoid Arthritis; Role; SELL gene; Spleen; Surface; Syndrome; System; T-Cell Activation; T-Cell Depletion; T-Lymphocyte; TNF-alpha converting enzyme; Testing; Theophylline; Therapeutic; Therapeutic immunosuppression; Time; Transgenic Mice; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1; Vasculitis; Veterans; Work; abstracting; alpha secretase; base; bone; chronic T-cell leukemia; cytokine; cytopenia; design; effective therapy; improved; in vivo; inhibitor/antagonist; lymph nodes; meetings; migration; mouse model; novel therapeutics; pre-clinical; preclinical study; progenitor; public health relevance; receptor; research study; trafficking; treatment strategy

DESCRIPTION (provided by applicant): Abstract: Clonal diseases of large granular lymphocytes (LGL) are characterized by lymphocytosis and T cell-mediated cytopenias of the myeloid compartment. Several syndromes of T cell-mediated bone marrow failure have similar pathology including aplastic anemia (AA), paroxysmal nocturnal hemaglobinuria (PNH), and a subset of patients with Myelodysplastic Syndrome (MDS). All of these syndromes are characterized by clinical improvement with immunosuppressive therapy (IST) such as low-dose methotrexate (MTX), low- dose cyclophosphamide (CY) or cyclosporine A (CyA) and, in the case of aplastic anemia and MDS, T cell depletion with anti-thymocyte globulin (ATG). The broad long-term goal of this proposal is to improve the diagnosis and treatment of patients with LGL leukemia and these other bone marrow failure diseases. In patients with these T-cell mediated bone marrow failure syndromes, it is not clear whether the T lymphocytes become activated locally in the bone marrow against specific bone marrow antigens, or within the peripheral lymphoid system and then home to the bone marrow. The prevailing idea during the last funding period was that an antigen, presumably a common antigen on myeloid progenitors was responsible for suppression of myelopoiesis. This was thought to be due to the direct interaction between this "putative myeloid-specific antigen" and the expanded antigen-specific T cell clone. In the Progress Report, our data strongly suggests that a multi-step model of autoimmunity for this disease process based on work during the last funding period. We show in preliminary results that the lymph node homing receptor L-selectin (CD62L) is dramatically lost from CD8+ T cells in LGL leukemia patients (manuscript published in Blood 2009). The main hypothesis to be addressed in this proposal is that altered bone marrow homing is critical for LGL leukemia pathogenesis. We hypothesize that acute activation in the primary lymphoid system leads to cleavage and shedding of CD62L by the Tumor Necrosis Factor-1 Converting Enzyme (TACE), which also known as ADAM-17. This matrix metalloproteinase (MMP) cleaves not only CD62L to control the egress of T cells from the lymph node but it is also necessary for the activity of several inflammatory cytokines with known importance in LGL leukemia and other autoimmune diseases. In Specific Aim 1, we will confirm our hypothesis that loss of CD62L expression is mediated primarily by ectodomain shedding by the ADAM-17 matrix metalloproteinase. Because CD62L is a lymphoid homing receptor, we hypothesize that loss of this receptor then allows these activated T cells to exit the lymph node but loss of CD62L alone is not expected to trigger migration and colonization in the bone marrow where these cells suppress hematopoiesis. The focus of Specific Aim 2 is to determine the mechanism of bone marrow homing by T cells in LGL leukemia using an in vitro system. Homing and migration are complex events that are optimally monitored in vivo and there is no mouse model of LGL leukemia or bone marrow failure disease currently available. Moreover, the regulation of homing to the bone marrow even under normal conditions is incompletely understood. Since the antigen that activates T cells in LGL leukemia is unknown, we will use a well defined transgenic mouse model to study important aspects of bone marrow homing and hemosuppression by antigen-specific T cells. This will allow us to test the importance of CD62L, VLA-4, and ADAM-17 in vivo. Additionally, the efficacy of pharmacological inhibitors to block homing to the bone marrow will be tested to provide critical pre-clinical data for application to clinical studies in patients in the future. PUBLIC HEALTH RELEVANCE: Large granular lymphocyte (LGL) leukemia occurs primarily in older individuals and is associated with poor blood formation. Blood counts have been shown to recover in some patients after treatment with therapies that block an over active immune response. Despite the fact that patients may benefit from this form of treatment, a basic understanding of the abnormalities in the immune system is needed to understand why this form of treatment works in some patients and not others so that new and more effective therapies can be discovered. In our study, we show several important findings that possibly explain the problem in the immune system of some patients with LGL leukemia based on work from the last funding period. Our results show for the first time a model for this disease that is similar to other autoimmune diseases and lays out the foundation for a better understanding of immune defects that may lead to new therapies. We will expand on our early findings and perform experiments in the laboratory to uncover new target drug therapies based on blocking activated T cells from entering the bone marrow where they block blood formation. These studies will greatly impact the care of veterans with LGL leukemia and may also impact millions of patients with autoimmune diseases.

描述（由申请人提供）： 摘要：大颗粒状淋巴细胞（LGL）的克隆疾病的特征是淋巴细胞增多和T细胞介导的髓样区室的细胞质。 T细胞介导的骨髓衰竭的几种综合征具有相似的病理学，包括性障碍性贫血（AA），阵发性的夜间血红蛋白尿症（PNH）和骨髓增生性综合征（MDS）的一部分。所有这些综合征的特征在于通过免疫抑制治疗（IST）改善临床改善（例如低剂量甲氨蝶呤（MTX），低剂量的环磷酰胺（CY）或环孢素A（CYA），而在抗血症和MDS的情况下，与抗甲状腺素（At-Globhymocyte）（ATG）（ATG）（ATG）（ATG）（ATG）（ATG）（at）depletion（cya）。该提案的长期长期目标是改善LGL白血病患者和其他骨髓衰竭疾病的诊断和治疗。 在患有这些T细胞介导的骨髓衰竭综合征的患者中，尚不清楚T淋巴细胞是在骨髓中局部激活的针对特定的骨髓抗原，还是在外周淋巴机系统中，然后在骨髓中回家。在最后一个资金期间，普遍的想法是，骨髓祖细胞上的一种抗原，大概是一种常见的抗原，负责抑制骨髓病。人们认为这是由于这种“推定的髓样特异性抗原”与扩展的抗原特异性T细胞克隆之间的直接相互作用。在进度报告中，我们的数据强烈表明，基于上一个资金期间工作的这种疾病过程的自身免疫的多步模型。我们在初步的结果中表明，在LGL白血病患者的CD8+ T细胞中，淋巴结归因受体L-选择素（CD62L）巨大损失（手稿在血液中发表于2009年）。该提案中要解决的主要假设是，改变的骨髓归巢对于LGL白血病发病机理至关重要。我们假设一级淋巴系统中的急性激活导致肿瘤坏死因子1转化酶（TACE）对CD62L的切割和脱落，这也称为ADAM-17。该基质金属蛋白酶（MMP）不仅裂解CD62L以控制T细胞从淋巴结中的出口，而且对于几种在LGL白血病和其他自身免疫性疾病中已知重要性的炎性细胞因子的活性也是必要的。在特定的目标1中，我们将确认我们的假设，即CD62L表达的丧失主要是由ADAM-17基质金属蛋白酶脱落的胞外域脱落。由于CD62L是一种淋巴样归纳受体，因此我们假设该受体的丧失允许这些活化的T细胞退出淋巴结，但预计单独的CD62L的损失不会触发这些细胞抑制造血的骨髓中的骨髓中的迁移和定殖。特定目的2的重点是确定使用体外系统T细胞在LGL白血病中T细胞的骨髓归住的机理。归巢和迁移是在体内最佳监测的复杂事件，目前没有LGL白血病或骨髓衰竭疾病的小鼠模型。此外，即使在正常条件下，也无法完全理解归巢的调节。由于激活LGL白血病中T细胞的抗原尚不清楚，因此我们将使用明确定义的转基因小鼠模型来研究抗原特异性T细胞的骨髓归巢和血压抑制的重要方面。这将使我们能够测试体内CD62L，VLA-4和ADAM-17的重要性。此外，将测试药理学抑制剂阻止骨髓归巢的功效，以提供关键的临床前数据，以便将来在患者的临床研究中应用。 公共卫生相关性： 大颗粒状淋巴细胞（LGL）白血病主要发生在老年人中，与血液形成不良有关。在治疗疗法后，一些患者的血数已被证明可以恢复，以阻止过度的免疫反应。尽管患者可能会从这种形式的治疗中受益，但仍需要对免疫系统异常的基本理解，以了解为什么这种形式的治疗形式在某些患者而不是其他患者中起作用，以便可以发现新的，更有效的疗法。在我们的研究中，我们展示了一些重要发现，这些发现可能会根据上次融资期的工作来解释一些LGL白血病患者的免疫系统中的问题。我们的结果首次表明，该疾病的模型与其他自身免疫性疾病类似，并为更好地理解可能导致新疗法的免疫缺陷奠定了基础。我们将扩大我们的早期发现，并在实验室进行实验，以发现基于阻断活化的T细胞进入骨髓的新目标药物疗法，从而阻断血液形成。这些研究将极大地影响LGL白血病退伍军人的护理，也可能影响数百万自身免疫性疾病的患者。