Macrophage Produced Phospholipid Transfer Protein (PLTP)

巨噬细胞产生磷脂转移蛋白 (PLTP)

• 批准号: 8111498
• 负责人: Linda K Curtiss
• 金额: $ 28.43万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-15 至 2013-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8111498
• 关键词: ATP-Binding Cassette Transporters; Acute-Phase Proteins; Affect; Agonist; Anti-Inflammatory Agents; Anti-inflammatory; Antisense Oligonucleotides; Aorta; Arterial Fatty Streak; Atherosclerosis; Binding; Bone Marrow; Bone Marrow Cells; Bone Marrow Transplantation; Cell membrane; Cells; Cholesterol; Chronic; Chronic Disease; Complement; Coronary heart disease; Diabetes Mellitus; Diet; Dimerization; Disease; Endosomes; Energy Transfer; Event; Exhibits; Fatty acid glycerol esters; Gene Expression; Genes; Goals; Heart; Hepatic; Hepatocyte; High Density Lipoprotein Cholesterol; Human; In Vitro; Inflammation; Inflammatory; Inflammatory Response; Lasers; Lead; Lesion; Leukocytes; Lipids; Lipoproteins; Liver; Mediating; Membrane; Membrane Microdomains; Microscopy; Monitor; Mus; Pathway interactions; Phospholipid Transfer Proteins; Phospholipids; Physiological; Physiology; Plasma; Play; Poly I-C; Production; Regulation; Reporting; Research; Risk Factors; Role; Scanning; Signal Transduction; Signal Transduction Pathway; Sinus; Sterols; TLR2 gene; TLR3 gene; TNF gene; Testing; Therapeutic; Tissues; Yang; atherogenesis; atheroprotective; autocrine; base; cardiovascular risk factor; cytokine; dimer; feeding; improved; in vivo; interstitial; macrophage; mouse model; mutant; novel; overexpression; paracrine; plasma phospholipid transfer protein; reconstitution; response; sound

DESCRIPTION (provided by applicant): Macrophages (MF) play a central role in atherogenesis through accumulation of lipids and production of inflammatory cytokines. Plasma phospholipid transfer protein (PLTP) is associated with MF in lesions and its' expression is up-regulated by lipid loading. We reported that PLTP produced within lesions is atheroprotective. The long-term goal of this project is to identify mechanisms whereby cell associated PLTP is anti-inflammatory and atheroprotective. The first aim will test the hypothesis that MF PLTP disrupts TLR2/1 plasma membrane dimerization and signaling, but not preformed TLR3 dimer mediated signaling in endosomes. We will assess the anti-inflammatory effects of MF PLTP on TLR2/1 and TLR3 signaling in PLTP- /-LDLr-/- mice irradiated and reconstituted with bone-marrow (BM) from PLTP+/+ or PLTP-/- mice. Cytokine production and atherosclerosis will be studied. The second aim will test the hypothesis that PLTP alters cholesterol dependent membrane domains (lipid rafts). We will determine if wild-type (WT) or mutant PLTP (which binds ABCA1 but lacks lipid transfer activity) disrupts lipid rafts and/or inhibits TLR2/1 dimerization in vivo and in vitro. The third aim will test the idea that reduced hepatic production of PLTP to reduce plasma levels of PLTP will favor the beneficial effects of cell associated PLTP. We will assess the anti-inflammatory effects of PLTP on TLR2 signaling in LDLr-/- mice with suppressed, but not deleted, hepatic PLTP. This will be accomplished with in vivo administration of mouse PLTP antisense oligonucleotides (ASO). Novel, targeted mouse models for study of chronic inflammation are used to establish the physiological significance of our hypotheses and will be complemented by in vitro studies to identify the mechanisms involved in these physiological events. Laser scanning confocal immunofluorescent microscopy is used to characterize early atherosclerosis progression. Fluorescent resonance energy transfer (FRET) is used to characterize changes in lipid rafts in response to PLTP. Finally, the proposed studies will use antisense oligonucleotides (ASO) to favor the beneficial effects of anti-inflammatory cellular PLTP while reducing the undesirable affects of circulating plasma PLTP. It is imperative that we now know whether cell-directed or plasma-directed PLTP atheroprotective therapeutics should be pursued for human treatment of cardiovascular risk factors. PUBLIC HEALTH RELEVANCE: The proposed studies will significantly alter the direction of PLTP research by providing sound evidence of its role in the regulation of intracellular inflammatory pathways. The results of our studies will lead to a new and improved understanding of MF physiology and inflammation thus providing the bases for novel treatment options for atherosclerosis, diabetes and other chronic diseases that have a strong inflammatory component.

描述（由申请人提供）：巨噬细胞（MF）通过脂质的积累和炎症细胞因子的产生在动脉粥样硬化形成中发挥核心作用。血浆磷脂转移蛋白 (PLTP) 与病变中的 MF 相关，其表达会因脂质负荷而上调。我们报道了病变内产生的 PLTP 具有动脉粥样硬化保护作用。该项目的长期目标是确定细胞相关 PLTP 抗炎和动脉粥样硬化的机制。第一个目标将测试以下假设：MF PLTP 会破坏 TLR2/1 质膜二聚化和信号传导，但不会破坏内体中预先形成的 TLR3 二聚体介导的信号传导。我们将评估 MF PLTP 对经 PLTP+/+ 或 PLTP-/- 小鼠骨髓 (BM) 照射和重建的 PLTP-/-LDLr-/- 小鼠中 TLR2/1 和 TLR3 信号传导的抗炎作用。将研究细胞因子的产生和动脉粥样硬化。第二个目标将检验 PLTP 改变胆固醇依赖性膜域（脂筏）的假设。我们将确定野生型 (WT) 或突变型 PLTP（结合 ABCA1 但缺乏脂质转移活性）是否会在体内和体外破坏脂筏和/或抑制 TLR2/1 二聚化。第三个目标将测试以下观点：减少肝脏产生 PLTP 以降低血浆 PLTP 水平将有利于细胞相关 PLTP 的有益作用。我们将评估 PLTP 对肝脏 PLTP 受到抑制但未删除的 LDLr-/- 小鼠中 TLR2 信号传导的抗炎作用。这将通过体内施用小鼠 PLTP 反义寡核苷酸 (ASO) 来实现。用于研究慢性炎症的新型靶向小鼠模型用于建立我们假设的生理意义，并将通过体外研究进行补充，以确定这些生理事件所涉及的机制。激光扫描共聚焦免疫荧光显微镜用于表征早期动脉粥样硬化进展。荧光共振能量转移 (FRET) 用于表征脂筏响应 PLTP 的变化。最后，拟议的研究将使用反义寡核苷酸（ASO）来促进抗炎细胞 PLTP 的有益作用，同时减少循环血浆 PLTP 的不良影响。我们现在必须知道是否应该采用细胞定向或血浆定向 PLTP 动脉粥样硬化疗法来治疗人类心血管危险因素。 公共健康相关性：拟议的研究将通过提供其在细胞内炎症途径调节中的作用的可靠证据来显着改变 PLTP 研究的方向。我们的研究结果将带来对 MF 生理学和炎症的新的、更好的理解，从而为动脉粥样硬化、糖尿病和其他具有强烈炎症成分的慢性疾病的新治疗方案奠定基础。