Novel hematopoietic effects of C5 cleavage fragment

C5 裂解片段的新造血作用

• 批准号: 8431861
• 负责人: Mariusz Z Ratajczak
• 金额: $ 34.15万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-01 至 2017-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8431861
• 关键词: Address; Adhesions; Adult; Anaphylatoxins; Blood Vessels; Bone Marrow; Bone Marrow Cells; Bone Marrow Transplantation; CXCR4 Receptors; CXCR4 gene; Cell Adhesion Molecules; Cells; Chemotactic Factors; Circadian Rhythms; Collaborations; Complement; Complement 3a; Complement 5a; Complement Activation; Complement Membrane Attack Complex; Complement component C5; Cytolysis; Data; Defect; Development; Dinoprostone; Distal; Endothelium; Engraftment; Erythrocytes; Exhibits; Fibroblasts; Funding; Generations; Granulocyte Colony-Stimulating Factor; Growth Factor; Hematopoiesis; Hematopoietic; Hematopoietic Stem Cell Mobilization; Hematopoietic Stem Cell Transplantation; Hematopoietic stem cells; Homing; Human; Integrin alpha4beta1; Integrins; Investigation; Lead; Life; Ligands; Light; Link; Lipids; Lytic; Molecular; Mus; Natural Immunity; Nucleotides; Osteoblasts; Patients; Physiological; Plasma; Polysaccharides; Process; Publishing; Role; Stem cells; Syndrome; Testing; Transplantation; Transplantation Conditioning; Umbilical Cord Blood; Vascular Cell Adhesion Molecule-1; Work; base; cathelicidin; ceramide 1-phosphate; chemotherapy; complement C3 precursor; complement C5b; immunodeficient mouse model; leukemia; novel; novel therapeutics; peripheral blood; public health relevance; reconstitution; response; sphingosine 1-phosphate; stem; trafficking

DESCRIPTION (provided by applicant): Both pharmacological mobilization of hematopoietic stem progenitor cells (HSPCs) and myeloablative conditioning for transplantation activate the complement cascade (CC) in bone marrow (BM), and in the previous funding period we focused on the role of the third complement component (C3) in mobilization and homing of HSPCs. In this competing renewal we will focus on the fifth complement component (C5), which is located downstream from C3. C5 cleavage leads to generation of the potent anaphylatoxins C5a and desArgC5a and generation of non-lytic and lytic C5b-C9, known as the membrane attack complex (MAC). Our recently published data support a crucial role for C5a/C5b-C9 in trafficking of HSPCs. In particular, C5-deficient mice are poor mobilizers in response to granulocyte colony stimulating factor (G-CSF) and exhibit delayed hematopoietic reconstitution after transplantation with wild type (WT) BM cells. Based on these findings, the central hypothesis of this competing renewal is that the activation of distal steps of the complement cascade and release of C5a and C5b-C9 (MAC) are important regulators of mobilization and homing of HSPCs. To address this hypothesis, we propose: Specific Aim 1. The molecular basis of the mobilization defect in C5-deficient mice. Based on our observation that C5-deficient mice are poor G-CSF mobilizers, we will address whether C5 cleavage is i) required for circadian HSPC mobilization, ii) mobilization of HSPC induced by other agents and iii) whether C5 activation and S1P plasma level correlates with mobilization efficacy in patients. We will also focus on the role of erythrocyte-released S1P in mobilization by performing mobilization studies in CD55/CD59-deficient mice that are highly sensitive to C5b-C9 (MAC) lysis. Finally, we will focus on the role of C5b-C9-induced release of S1P in mobilization observed in patients with hemolytic syndromes. Specific Aim 2. The molecular basis of the homing defect in C5-deficient mice. We found that the CC is activated in lethally irradiated mice and that C5-deficient mice engraft poorly with WT BM cells. To shed more light on the role of the distal part of the CC (C5a/C5b-C9) in homing/engraftment, we will study whether conditioning for transplantation by chemotherapy also activates the CC in BM and study the effect of C5a/C5b-C9 on expression of i) HSPC chemoattractants in BM, ii) adhesion/tethering molecules for HSPCs on BM endothelium, and ii) on secretion of factors facilitating homing. Specific Aim 3. The C5a/C5b-C9-induced BM stroma-derived cathelicidin (LL-37) as a potent homing sensitizing factor. We found that LL-37, like C3a, is a very strong priming factor for SDF-1 that becomes upregulated in BM stroma after conditioning for transplantation in a C5a/C5b-C9-dependent manner. In an immunodeficient mouse model, we will test whether short exposure of HSPCs to LL-37 before transplantation increases homing of human BM- and umbilical cord blood (UCB)-derived HSPCs. We will also address whether LL-37 also primes the responsiveness of HSPCs to other homing factors and focus on the molecular mechanism of these phenomena.

描述（由申请人提供）：造血干细胞祖细胞（HSPCs）的药理动员和移植的清髓调节均可激活骨髓（BM）中的补体级联（CC），在之前的资助期内，我们重点研究了第三补体成分（C3）在HSPCs的动员和归巢中的作用。在这个竞争性更新中，我们将重点关注位于C3下游的第五个补体成分（C5）。C5的裂解导致强效过敏毒素C5a和desArgC5a的产生，以及非裂解性和裂解性C5b-C9的产生，称为膜攻击复合物（MAC）。我们最近公布的数据支持C5a/C5b-C9在HSPCs贩运中发挥关键作用。特别是，c5缺陷小鼠对粒细胞集落刺激因子（G-CSF）的动员反应较差，并且在野生型（WT） BM细胞移植后表现出延迟的造血重建。基于这些发现，这种竞争性更新的中心假设是补体级联远端步骤的激活和C5a和C5b-C9 （MAC）的释放是HSPCs动员和归巢的重要调节因子。为了解决这一假设，我们提出：c5缺陷小鼠动员缺陷的分子基础。基于我们对C5缺陷小鼠G-CSF动员能力较差的观察，我们将探讨C5裂解是否为i)昼夜HSPC动员所必需，ii)其他药物诱导的HSPC动员，以及iii) C5激活和血浆中S1P水平是否与患者的动员效果相关。我们还将通过对C5b-C9 （MAC）裂解高度敏感的CD55/ cd59缺陷小鼠进行动员研究，关注红细胞释放的S1P在动员中的作用。最后，我们将重点关注c5b - c9诱导的S1P释放在溶血综合征患者中观察到的动员中的作用。具体目标2。c5缺陷小鼠归巢缺陷的分子基础。我们发现，在致命辐射小鼠中，CC被激活，并且c5缺陷小鼠移植WT - BM细胞的能力较差。为了进一步阐明CC远端部分（C5a/C5b-C9）在归巢/移植中的作用，我们将研究化疗对移植的调节是否也激活BM中的CC，并研究C5a/C5b-C9对i) BM中HSPC化学引诱剂表达的影响，ii) HSPC在BM内皮上的粘附/系固分子，以及ii)促进归巢因子分泌的影响。具体目标3。C5a/ c5b - c9诱导BM基质源性cathelicidin （LL-37）是一种有效的归巢增敏因子。我们发现LL-37和C3a一样，是一个非常强的SDF-1的启动因子，在移植后以C5a/ c5b - c9依赖的方式在骨髓基质中上调。在免疫缺陷小鼠模型中，我们将测试移植前短时间暴露于LL-37的HSPCs是否会增加人骨髓和脐带血（UCB）来源的HSPCs的归家。我们还将探讨LL-37是否也启动了HSPCs对其他归巢因子的响应性，并重点研究这些现象的分子机制。