血小板中可溶性CD40L的释放受糖蛋白IIb/IIIa和肌动蛋白聚合作用的调节。

Release of soluble CD40L from platelets is regulated by glycoprotein IIb/IIIa and actin polymerization.

作者信息

Furman Mark I, Krueger Lori A, Linden Matthew D, Barnard Marc R, Frelinger Andrew L, Michelson Alan D

机构信息

Center for Platelet Function Studies, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.

出版信息

J Am Coll Cardiol. 2004 Jun 16;43(12):2319-25. doi: 10.1016/j.jacc.2003.12.055.

DOI:10.1016/j.jacc.2003.12.055

PMID:15193700

Abstract

OBJECTIVES

The purpose of this study was to examine the effects of glycoprotein (GP) IIb/IIIa antagonists (abciximab, eptifibatide, and tirofiban) and other inhibitors on translocation of CD40L from intraplatelet stores to the platelet surface and on the release of soluble CD40L (sCD40L) from platelets.

BACKGROUND

CD40L is a proinflammatory and prothrombotic ligand in the tumor necrosis factor family.

METHODS

Platelet surface CD40L was measured by flow cytometry, and sCD40L was measured by enzyme-linked immunosorbent assay.

RESULTS

Translocation of CD40L from intraplatelet stores to the platelet surface was not inhibited by GP IIb/IIIa antagonists. However, release of sCD40L from the surface of activated platelets was inhibited by GP IIb/IIIa antagonists in a dose-dependent manner, in concert with inhibition of PAC1 binding to platelets (a surrogate marker for fibrinogen binding). Release of sCD40L from activated platelets was also markedly reduced in Glanzmann platelets (deficient in GP IIb/IIIa). Ethylenediaminetetraacetic acid was an effective inhibitor of sCD40L release, but only when added before platelet activation. Both cytochalasin D (an inhibitor of actin polymerization) and GM6001 (an inhibitor of matrix metalloproteinases [MMPs]) inhibited the release of sCD40L from platelets when added before, as well as 3 min after, platelet activation. However, neither cytochalasin D nor GM6001 affected translocation of CD40L to the platelet surface.

CONCLUSIONS

The GP IIb/IIIa antagonists inhibit release of sCD40L from activated platelets. Release of sCD40L from platelets is regulated, at least in part, by GP IIb/IIIa, actin polymerization, and an MMP inhibitor-sensitive pathway. In addition to their well-characterized inhibition of platelet aggregation, GP IIb/IIIa antagonists may obviate the proinflammatory and prothrombotic effects of sCD40L.

摘要

目的

本研究旨在探讨糖蛋白（GP）IIb/IIIa拮抗剂（阿昔单抗、依替巴肽和替罗非班）及其他抑制剂对CD40L从血小板内储存部位转位至血小板表面以及对血小板释放可溶性CD40L（sCD40L）的影响。

背景

CD40L是肿瘤坏死因子家族中的一种促炎和促血栓形成配体。

方法

采用流式细胞术检测血小板表面CD40L，采用酶联免疫吸附测定法检测sCD40L。

结果

GP IIb/IIIa拮抗剂未抑制CD40L从血小板内储存部位转位至血小板表面。然而，GP IIb/IIIa拮抗剂以剂量依赖方式抑制活化血小板表面sCD40L的释放，同时抑制PAC1与血小板的结合（纤维蛋白原结合的替代标志物）。在Glanzmann血小板（缺乏GP IIb/IIIa）中，活化血小板释放的sCD40L也显著减少。乙二胺四乙酸是sCD40L释放的有效抑制剂，但仅在血小板活化前添加时有效。细胞松弛素D（肌动蛋白聚合抑制剂）和GM6001（基质金属蛋白酶[MMPs]抑制剂）在血小板活化前以及活化后3分钟添加时均抑制血小板释放sCD40L。然而，细胞松弛素D和GM6001均不影响CD40L转位至血小板表面。