TLR4 and murine ischemic acute renal failure

TLR4 与小鼠缺血性急性肾衰竭

• 批准号: 7433821
• 负责人: CHRISTOPHER Y. LU
• 金额: $ 30.63万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-04 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7433821
• 关键词: Acute Kidney Failure; Area; Bone Marrow; Bone Marrow Transplantation; Cells; Chimera organism; Complement; Condition; Cultured Cells; Data; Disease; Dissection; Endothelium; Endotoxins; Gene Activation; Genes; Gram-Negative Bacteria; Heat shock proteins; In Situ Hybridization; In Vitro; Inflammation; Inflammatory Response; Injury; Ischemia; Kidney; Lasers; Leukocytes; Ligands; Ligation; Mammalian Cell; Marrow; Mediating; Microarray Analysis; Morphologic artifacts; Mus; Population; Recruitment Activity; Regulation; Renal tubule structure; Role; Signal Transduction; Solid; Staging; System; TLR4 gene; Testing; Tubular formation; base; cytokine; graft vs host disease; in vivo; injured; insight; loss of function mutation; macrophage; mortality; novel; novel strategies; prevent; research study

DESCRIPTION (provided by applicant): We recently found that two different loss-of-function mutations of TLR4 decrease ischemic acute renal failure (ARF). Using bone marrow chimeras, immunohistology, and in situ hybridization, we also found that maximal ischemic ARF required TLR4 on infiltrating leukocytes (probably macrophages), and. on endothelia of the vasa rectae and tubules of the outer medulla. The latter is in the area where there is maximal injury and inflammation. Based on the above, we formulated the following hypothesis. Endogenous TLR4 ligands (possibly heat shock proteins) are released from injured renal tubules after ischemia. These activate the endothelia of the outer medulla and renal tubules. The activated endothelia and tubules help recruit an inflammatory response. The infiltrating leukocytes are further activated, via their TLR4, to release toxic molecules that exacerbate injury. Three Specific Aims test this hypothesis. Aim I) Determine what genes are regulated by endothelial and tubular TLR4 by using immunohistology, in situ hybridization, and laser capture dissection followed by microarray analysis. We will use hypothesis- and microarray- driven approaches. We will compare expression of the putative TLR4-regulated genes in TLR4-sufficient and -deficient mice. Aim II) Use bone- marrow chimeras (lethally irradiated mice, which have been rescued by bone-marrow transplants) to study intermediate stages of inflammation that culminate in maximal ischemic ARF. Aim III) Use in vitro systems to identify and study the endogenous TLR4 ligands. Identify the TLR4 ligands. Use in vitro systems to study the regulation of TLR4 expression on endothelia/ tubules, and to study the genes regulated by TLR4 in these cells. These in vitro experiments complement the in vivo experiments of "Specific Aims I & II". We will use stringent precautions to prevent endotoxin contamination in these experiments. Altogether, this is a novel approach to ischemic ARF and may yield new insights and therapies of a disease that continues, despite modern therapy, to have a high mortality.

描述（由申请人提供）：我们最近发现TLR 4的两种不同的功能丧失突变减少缺血性急性肾衰竭（ARF）。利用骨髓嵌合体、免疫组织学和原位杂交，我们还发现最大缺血性ARF需要浸润白细胞（可能是巨噬细胞）上的TLR 4，并且。对直血管内皮和外髓质小管的影响。后者位于损伤和炎症最严重的区域。基于上述情况，我们提出了以下假设。缺血后，损伤的肾小管释放出内源性TLR 4配体（可能是热休克蛋白）。这些激活外髓质和肾小管的内皮。激活的内皮细胞和小管有助于引发炎症反应。浸润的白细胞通过它们的TLR 4被进一步激活，以释放加重损伤的毒性分子。三个具体目标验证了这一假设。目的I）通过免疫组织学、原位杂交、激光捕获切割和微阵列分析确定哪些基因受内皮和肾小管TLR 4的调控。我们将使用假设和微阵列驱动的方法。我们将比较假定的TLR 4调节基因在TLR 4充足和缺乏小鼠中的表达。目的II）使用骨髓嵌合体（经致死性照射的小鼠，其已被骨髓移植挽救）来研究最终导致最大缺血性ARF的炎症的中间阶段。目的III）利用体外系统鉴定和研究内源性TLR 4配体。识别TLR 4配体。利用体外系统研究TLR 4对内皮/肾小管表达的调控，并研究TLR 4在这些细胞中调控的基因。这些体外实验补充了“具体目标I和II”的体内实验。我们将采取严格的预防措施，以防止这些实验中的内毒素污染。总之，这是一种治疗缺血性ARF的新方法，可能会产生新的见解和治疗方法，尽管有现代治疗，这种疾病仍然具有高死亡率。