Role of Endotoxin-binding proteins in Non-specific Protection to Infection

内毒素结合蛋白在非特异性感染保护中的作用

• 批准号: 04670250
• 负责人: HIRATA Michimasa
• 金额: $ 1.34万
• 依托单位: Iwate Medical University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04670250/
• 关键词: Lipopolysaccharide(LPS); LPS-binding protein; Tissue factor; Disseminated intravascular coagulation; Anticoagulant; Antibacteria; LPS-neutralization; リポ多種(LPS); LPS中和; 酸化窒素; 腫瘍壊死因子; エンドトキシンショック

Endotoxin(lipopolysaccharide=LPS), cell wall component of gram-negative bacteria, activates monocytes and macrophages to release cytokines, reactive nitrogen intermediates (RNI), and to generate tissue factor(TF) which initiate coagulation. We have purified 7kDa and 18kDa cationic antibacterial proteins (CAP-7 and CAP-18) with LPS-binding and LPS-neutralizing activities from rabbit granulocytes using as an assay the agglutination of erythrocytes coated with Re-LPS.From protein sequencing, CAP-7 was identified as the C-terminal 37 amino acid fragment of CAP-18. Synthetic peptide #197(identical sequence to CAP-7, Gly1-Try37) and #36-1 (a truncation of CAP consisting of 32 amino acid residues, Gly1-Ala32) showed LPS-binding activity. Each peptide inhibited LPS-induced tissue factor(TF) generation by murine peritoneal macrophages, even added 1 hour after stimulation of cells with LPS.C57BL/6 mice treated with #197 were significantly protected from lethal LPS challenge. Peptide #36 also blo … More cked the LPS-induced lethality. These peptides had antibacterial activity to gram-negative bacteria, such as E.coli, S.typhimurium, K.pneumonia, Ps.aeruginosa and also to gram-positive S.aureus(Methicllin sensitive and resistant strains). Both peptides inhibited TF-and Xa-induced plasma clotting. Using synthetic chromogenic substrates, both CAP7 peptides blocked the coagulation cascade at two sites, activation of factor X to Xa and conversion of Factor II(prothrombin) to factor IIa(prothrombin). In vivo treatment of peptide #197 prevented acute lethality in mice injected with tissue factor (rabbit brain thromboplastin). Two other peptides, #32(Gly1-Phe9) and #50(lle13-Typ37) failed to demonstrate LPS-binding, LPS-neutralizing, antibacterial and anticoagulant activities. The active peptides but not the inactive peptide maintain a putative heparin binding domain at their N-termini. This heparin binding domain is participate in the LPS-binding, LPS neutralizing, antibacterial and anticoaThese active peptides may have a therapeutic potential for treatment for DIC due to sepsis and endotoxin shock. Less

内毒素（脂多糖= LPS），革兰氏阴性细菌的细胞壁成分，激活单核细胞和巨噬细胞释放，活跃的氮中间体（RNI），并产生组织因子（TF）（TF）蛋白质（CAP-7和CAP-18），使用Asay分析的兔子粒细胞中具有LPS结合和LPS中和活性的蛋白质，使用cap-7鉴定为cap-7，cap-7被鉴定为Cap-7 CAP-18的氨基酸片段。受到致命的LPS挑战＃36，也有更多的CK诱导的致死性。潮汐在两个坐骨上阻塞了凝血级数，将因子X激活到Xa，并将因子II（凝血酶原）转化为IIA因子（凝血酶原）。另外两个肽，即＃32（Gly1-Phe9）和＃50（LLE13-TYP37）未能证明LPS结合，LPS中和，抗细菌的凝固肽，但没有使无效的肝素在其N-N-N-N-N-N-N-N-N-N-N-末端。该肝素结合结构域参与LPS结合，LPS中和，抗菌和抗菌活性肽可能会因败血症和内毒素休克而具有治疗的治疗潜力

项目成果

Hirata, M., Shimomura, Y., Yoshida, M., Morgan, J.G., Palings, I., Wilson D., Yen, M.H. : and Larrick, J.W.: "Characterization of a rabbit cationic protein (CAP-18) with lipopolysaccharide-inhibitory activity" Infect.Immun. (in press). (1994)

平田 M.、下村 Y.、吉田 M.、摩根 J.G.、帕林斯 I.、威尔逊 D.、日元 M.H.

Hirata M.,Shimomura Y et al: "Endotoxin-neutralizing,antibacterial and anticoagulant activities rabbit CAP18-derived peptides." Gram Negative Sepsis:Basic Science to clinical Investigation. (in press). (1994)

Hirata M.、Shimomura Y 等人：“兔 CAP18 衍生肽具有中和、抗菌和抗凝血活性。”

Larrick.J.W,Hirata,Metsl: "A novelgranalocyte-derived peptide with LPS neutralizing activity" J.Immunol. 152. 231-240 (1994)

Larrick.J.W、Hirata、Metsl：“一种具有 LPS 中和活性的新型粒细胞衍生肽”J.Immunol。

平田 陸正: "内毒素結合蛋白質の構造と活性" 第39回毒素シンポジウム予稿集. 80-84 (1992)

Rikumasa Hirata：“内毒素结合蛋白的结构和活性”第 39 届毒素研讨会论文集 80-84（1992 年）。

Larrick,J.W.,Hirata,M et al: "A Novel granulocyte-derived peptide with LPS neutralizing activity" J Immunol. 152. 231-240 (1994)

Larrick,J.W.,Hirata,M 等人：“一种具有 LPS 中和活性的新型粒细胞衍生肽”JImmunol。