Molecular mechanism of lung discases by analysis of surfactant protein A and its receptor.

通过表面活性蛋白A及其受体分析肺疾病的分子机制。

• 批准号: 07457147
• 负责人: KUROKI Yoshio
• 金额: $ 0.83万
• 依托单位: Sapporo Medical University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07457147/
• 关键词: pulmonary surfactant; surfactant apoprotein A; C-type lectin; collectin family; lipid binding protein; host defense mechanism; alveolar type II cells; コレクチンファミリー; 脂質代謝調節

Pulmonary surfactant plays important roles in phospholipid homeostasis and in host deffence mechanism of the lung. In this research project, we focussed on surfactant ptotein A (SP-A) that belongs to collectin family which possesses the carbohydrate recognition domain, and on SP-A receptor. The purpose of this project was to investigate the molecular mechanisms of the lung discases in relation to SP-A.1. We examined the effect of SP-A on the interaction of phospholipid liposomes with plasma membrane isolated from alveolar type II cells. SP-A significantly facilitated the binding of liposomes to type II cell-derived membrane but not to liver plasma membrane. The results suggest that SP-A receptor on type II cells may be involved in facilitated effect of SP-A on liposome binding to membrane.2. Mannose-binding protein A (MBP-A) also belongs to the collectin subgroup of C-type lectins and structurally homologous to SP-A.We constructed chimeric molecules in which the SP-A region Glu^<195>-P … More he^<228> was substituted with the MBP-A region Glu^<185>-Ala^<221>. This chimera retained the ability to bind dipalmitoylphosphatidylcholine and interact with alveolar type II cells, while MBP-A isolated from rat sera failed to express these SP-A function. The results indicate that the SP-A region Glu^<195>-Phe^<228> and the MBP-A region Glu^<185>-Ala^<221> are interchangeable without loss of SP-A functions. The results from the recombinant proteins with point mutations also indicate that Arg^<199> and Lys^<201> of human SP-A and Lys^<201> and Lys^<203> of rat SP-A are not critical for the SP-A functions and that the crucial mechanism of SP-A-mediated liposome aggregation is distinct from that of SP-A-mediated lipid uptake by type II cells.3. The abnormal aggregates of SP-A oligomer derived from patients with alveolar type II cells was less effective in interaction with type II cells and exhibited abnormal phospholipid membrane organization. IgG was found to associate with the abnormal larger aggregates of SP-A oligomer but not with normal-sized SP-A.4. The analysis of SP-A gene and protein expression in cancer cells from pleural effusions of patients with lung adenocarcinomas revealed that more than three quaters of adenocarcinoma cells express SP-A,one of peripheral airway cell markers. Less

肺表面活性物质在肺磷脂平衡和宿主防御机制中起重要作用。本课题主要研究具有糖识别结构域的凝集素家族的表面活性剂蛋白A（SP-A）及其受体。本研究的目的是探讨SP-A. 1相关的肺部疾病的分子机制。我们研究了SP-A对磷脂脂质体与肺泡II型细胞质膜相互作用的影响。SP-A显著促进脂质体与II型细胞衍生膜的结合，但不促进脂质体与肝质膜的结合。结果提示，Ⅱ型细胞表面SP-A受体可能参与了SP-A促进脂质体与膜结合的作用.甘露糖结合蛋白A（MBP-A）也属于C型凝集素的凝集素亚群，与SP-A在结构上同源。<195> ...更多信息 用MBP-A区Glu ^-Ala ^取代。<228><185><221>这种嵌合体保留了结合二棕榈酰磷脂酰胆碱和肺泡II型细胞相互作用的能力，而从大鼠血清中分离的MBP-A未能表达这些SP-A功能。结果表明，SP-A区Glu ^-Phe ^和MBP-A区Glu ^-Ala ^是可互换的，SP-A功能没有丧失。<195><228><185><221>点突变重组蛋白的结果也表明人SP-A的Arg ^和Lys ^以及大鼠SP-A的Lys ^和Lys ^对于SP-A的功能不是关键的，并且SP-A介导的脂质体聚集的关键机制不同于SP-A介导的II型细胞的脂质摄取。<199><201><201><203>来自肺泡II型细胞患者的SP-A寡聚体的异常聚集体与II型细胞的相互作用效果较差，并表现出异常的磷脂膜组织。发现IgG与SP-A寡聚体的异常较大聚集体有关，但与正常大小的SP-A无关。4。对肺腺癌患者胸腔积液癌细胞中SP-A基因和蛋白表达的分析表明，超过四分之三的肺腺癌细胞表达外周气道细胞标志物之一的SP-A。少

项目成果

本田泰人: "特発性間質性肺炎における気管支肺胞洗浄液中サーファクタント蛋白質A(SP-A)値の検討" 日本胸部疾患学会誌. 34. 1326-1330 (1996)

Yasuto Honda：“特发性间质性肺炎支气管肺泡灌洗液中表面活性蛋白 A (SP-A) 水平的检查”日本胸科疾病学会杂志 34. 1326-1330 (1996)。

Honda, Y.: "Decreased contents of surfactant protein A and D in bronchoalveolar lavage fluids of healthy volunteers." Chest. 109. 1006-1009 (1996)

Honda, Y.：“健康志愿者的支气管肺泡灌洗液中表面活性蛋白 A 和 D 的含量降低。”

Hattori,A.: "Human surfactant protein A with two different oligomeric structures which exhibit different capacities to interact with alveolar type II cells" Biochem.J.317. 939-944 (1996)

Hattori,A.：“人类表面活性蛋白 A 具有两种不同的寡聚结构，表现出与 II 型肺泡细胞相互作用的不同能力”Biochem.J.317。

Thkahashi, H.: "Lipid analysis and surfactant-associated protein expression in lung adenocarcinoma cells from pleural effusion." Respiration. 63. 390-396 (1996)

Thkahashi, H.：“胸腔积液肺腺癌细胞中的脂质分析和表面活性剂相关蛋白表达。”

黒木由夫: "肺サーファクタントの生化学-アポ蛋白の構造と機能の解析-" 呼吸と循環. (印刷中). (1997)

Yoshio Kuroki：“肺表面活性物质的生物化学 - 脱辅基蛋白的结构和功能分析 -”呼吸与循环（出版中）。