Novel Functions of Red Cell Proteins Lu and LW

红细胞蛋白 Lu 和 LW 的新功能

基本信息

批准号：
7940838
负责人：
JOEL A CHASIS
金额：
$ 43.05万
依托单位：
UNIVERSITY OF CALIF-LAWRENC BERKELEY LAB
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-09-25 至 2012-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7940838
关键词：
Abnormal Red Blood Cell Acute Address Adhesions Adhesives Affect Affinity Amino Acids Anemia Antibodies Area Autoimmune Diseases Binding Binding Sites Biochemical Biological Assay Biology Blocking Antibodies Bone Marrow Cell Adhesion Cell Adhesion Molecules Cells Cytoplasmic Tail Cytoskeleton Data Defect Disease ECM receptor Erythroblasts Erythrocytes Erythroid Erythroid Cells Erythropoiesis Erythropoietin Exhibits Extracellular Matrix Fluorescent Probes Funding Glycoproteins Goals Hemorrhage Immunofluorescence Microscopy In Situ Inherited Integrins Island Knockout Mice Laminin Life Maps Marrow Mediating Mediator of activation protein Membrane Molecular Mus Mutagenesis Myelofibrosis Nature Output Pathology Physiological Play Polychromatophilic Erythroblast Production Proliferating Pronormoblasts Protein Isoforms Proteins RNA Splicing Relative (related person)Research Reticulocytes Role Sickle Cell Anemia Site Spectrin Staging Stress Structure Surface Techniques Testing Thalassemia Tissues Vascular Cell Adhesion Molecule-1 Wild Type Mouse Work base bioimaging biological adaptation to stress erythroid differentiation hematopoietic tissue human disease in vitro Assay in vivo insight macrophage migration mouse model novel protein function public health relevance reconstitution research study response synthetic peptide

项目摘要

DESCRIPTION (provided by applicant): The long-term objectives of our research are to develop a mechanistic understanding of how cell-cell and cell-extracellular matrix adhesive interactions regulate erythropoiesis. Erythroblasts differentiate in erythroblast islands, composed of erythroblasts surrounding a macrophage. However, little is known regarding the purpose of adhesive attachments in these erythroid niches. The goals of this application are to explore the function of adhesion molecules LW (termed ICAM-4) and Lutheran (Lu) glycoproteins. We have shown that erythroid islands are markedly decreased in ICAM-4 null bone marrow; ICAM-4/1V integrin adhesion mediates erythroblast-macrophage attachment; and normal but not Lu null erythroblasts bind matrix laminin in a differentiation stage-specific manner. We propose to 1) Explore the hypothesis that ICAM-4 is required for amplification of red blood cell production in stress erythropoiesis. After inducing erythropoietic stress, we will examine potential mechanisms for the deficient response in ICAM-4 knockout mice including: decreased proliferative potential; impaired recruitment of early stage erythroblasts to erythroid islands; and decreased island integrity. We will characterize erythroid proliferation and differentiation in the context of bone marrow and splenic islands employing live cell erythroid island assays, as well as colony assays, and erythroid island cultures. 2) Test the hypothesis that ICAM-4 has dual functions in erythroid islands by modulating both erythroblast-macrophage and erythroblast-erythroblast adhesion via interactions with different integrins. Building on preliminary evidence that erythroblasts bind ICAM-4 via 1421, we will identify the ICAM-4 site involved in 1421 binding; determine the effect on wild type and ICAM-4 null erythroid islands of blocking ICAM-4/1421 binding using fluorescent probes and bioimaging; and analyze whether inhibiting ICAM-4/1421 and ICAM-4/1V binding are additive. Mouse models for deficiency of marrow and splenic macrophages will also be employed to study the in vivo importance of erythroblast-macrophage interactions for erythropoiesis. 3) Explore whether Lu-laminin adhesion localizes erythroid islands to Laminin-containing regions in bone marrow and whether it regulates differentiation and/or proliferation. We will map the distribution of 15 laminin in bone marrow sections by immunofluorescence microscopy and determine its physical relationship to islands, comparing wild type and Lu knockout mice; and analyze and contrast proliferation and differentiation in Lu null and wild type mice by characterizing bone marrow islands and performing colony assays and erythroblast cultures in the presence and absence of laminin. The proposed objectives are relevant to obtaining an understanding of how red blood cell production is increased in response to multiple inherited and acquired anemias including sickle cell disease, hereditary membrane disorders, autoimmune red blood cell destruction and blood loss. They are also relevant to diseases associated with bone marrow fibrosis and abnormal red cell production. PUBLIC HEALTH RELEVANCE: These research objectives are relevant to obtaining increased understanding of how red blood cell production is increased in response to multiple inherited and acquired anemias including thalassemia, sickle cell disease, hereditary membrane disorders, autoimmune red blood cell destruction and blood loss. They are also relevant to diseases associated with bone marrow fibrosis and abnormal red blood cell production.

描述（由申请人提供）：我们的研究的长期目标是对细胞细胞和细胞 - 细胞基质基质粘合剂的相互作用如何调节红细胞生成的机械理解。红细胞在红细胞岛上有区别，由巨噬细胞周围的红细胞组成。但是，关于这些红系壁ni的粘合剂固定的目的知之甚少。该应用的目标是探索粘附分子LW（称为ICAM-4）和Lutheran（Lu）糖蛋白的功能。我们已经表明，ICAM-4无骨骨髓中的红细胞岛显着降低。 ICAM-4/1V整联蛋白粘附介导了红细胞巨噬细胞的附着；正常但不是lu null成红细胞以分化阶段特异性的方式结合基质层粘连蛋白。我们建议1）探讨以下假设：ICAM-4在压力红细胞生成中的红细胞产生是必需的。在诱导红细胞增压胁迫之后，我们将检查ICAM-4敲除小鼠反应不足的潜在机制，包括：增殖潜力降低；招募早期红细胞招募到红斑岛；并降低了岛屿的完整性。我们将在骨髓和脾群岛的背景下进行红细胞增殖和分化，这些骨髓和脾脏群岛采用了活细胞红斑岛分析，菌落分析以及红细胞岛文化。 2）检验以下假设：ICAM-4通过调节红细胞 - 巨噬细胞和红细胞 - 金细胞粘附，通过与不同的整合素的相互作用来调节红细胞巨噬细胞和红细胞 - 金细胞粘附。在初步证据的基础上，红细胞通过1421结合了ICAM-4，我们将确定涉及1421结合的ICAM-4位点；确定对使用荧光探针和生物成像的野生型和ICAM-4无效的ICAM-4/1421结合的影响；并分析抑制ICAM-4/1421和ICAM-4/1V结合是否是加性的。小鼠模型的骨髓和脾巨噬细胞的缺乏，还将用于研究红细胞巨噬细胞相互作用对红细胞生成的体内重要性。 3）探索Lu-Laminin粘附是否将骨髓中含层粘连蛋白的区域定位在含层粘连蛋白的区域以及是否调节分化和/或增殖。我们将通过免疫荧光显微镜绘制骨髓切片中15层粘连蛋白的分布，并确定其与岛屿的物理关系，以比较野生型和LU敲除小鼠。在存在和不存在层粘连蛋白的情况下，通过表征骨髓群岛并进行菌落测定和红细胞培养物，分析和对比度的增殖和分化。所提出的目标与了解如何增加了红细胞产生有关多种遗传和获得的贫血，包括镰状细胞疾病，遗传性膜疾病，自身免疫性红细胞破坏和失血。它们还与与骨髓纤维化和异常红细胞产生相关的疾病有关。公共卫生相关性：这些研究目标与对多种遗传性贫血有关，包括对红细胞的产生如何增加，包括thalassya，镰状细胞疾病，遗传性膜疾病，自身免疫性红细胞破坏和血液流失。它们也与与骨髓纤维化和异常红细胞产生相关的疾病有关。