Obi Andrea T, Andraska Elizabeth, Kanthi Yogendra, Kessinger Chase W, Elfline Megan, Luke Cathy, Siahaan Teruna J, Jaffer Farouc A, Wakefield Thomas W, Henke Peter K
Peter K. Henke, MD, University of Michigan Health System, 1500 E. Medical Center Drive, Cardiovascular Center - 5463, Ann Arbor, MI 48109-5867, USA, Tel.: +1 734 763 0250, Fax: +1 734 647 9867, E-mail:
Thromb Haemost. 2017 Jan 26;117(2):339-348. doi: 10.1160/TH16-03-0218. Epub 2016 Dec 15.
Venous thromboembolism is a major cause of death during and immediately post-sepsis. Venous thrombosis (VT) is mediated by cell adhesion molecules and leukocytes, including neutrophil extracellular traps (NETs). Sepsis, or experimentally, endotoxaemia, shares similar characteristics and is modulated via toll like receptor 4 (TLR4). This study was undertaken to determine if endotoxaemia potentiates early stasis thrombogenesis, and secondarily to determine the role of VT TLR4, ICAM-1 and neutrophils (PMNs). Wild-type (WT), ICAM-1 and TLR4 mice underwent treatment with saline or LPS (10 mg/kg i. p.) alone, or followed by inferior vena cava (IVC) ligation to generate stasis VT. In vivo microscopy of leukocyte trafficking was performed in non-thrombosed mice, and tissue and plasma were harvested during early VT formation. Pre-thrombosis, circulating ICAM-1 was elevated and increased leukocyte adhesion and rolling occurred on the IVC of LPS-treated mice. Post-thrombosis, endotoxaemic mice formed larger, platelet-poor thrombi. Endotoxaemic TLR4 mice did not have an augmented thrombotic response and exhibited significantly decreased circulating ICAM-1 compared to endotoxaemic WT controls. Endotoxaemic ICAM-1 mice had significantly smaller thrombi compared to controls. Hypothesising that PMNs localised to the inflamed endothelium were promoting thrombosis, PMN depletion using anti-Ly6G antibody was performed. Paradoxically, VT formed without PMNs was amplified, potentially related to endotoxaemia induced elevation of PAI-1 and circulating FXIII, and decreased uPA. Endotoxaemia enhanced early VT occurs in a TLR-4 and ICAM-1 dependent fashion, and is potentiated by neutropenia. ICAM-1 and/or TLR-4 inhibition may be a unique strategy to prevent sepsis-associated VT.
静脉血栓栓塞是脓毒症期间及脓毒症刚结束后的主要死亡原因。静脉血栓形成（VT）由细胞粘附分子和白细胞介导，包括中性粒细胞胞外陷阱（NETs）。脓毒症，或在实验中，内毒素血症，具有相似的特征，并通过Toll样受体4（TLR4）进行调节。本研究旨在确定内毒素血症是否会增强早期淤滞性血栓形成，其次确定VT TLR4、细胞间粘附分子-1（ICAM-1）和中性粒细胞（PMN）的作用。野生型（WT）、ICAM-1和TLR4小鼠分别接受单独的生理盐水或脂多糖（LPS，10mg/kg腹腔注射）治疗，或随后进行下腔静脉（IVC）结扎以产生淤滞性VT。对未形成血栓的小鼠进行白细胞运输的体内显微镜检查，并在早期VT形成过程中收集组织和血浆。血栓形成前，循环中的ICAM-1升高，LPS处理小鼠的IVC上白细胞粘附和滚动增加。血栓形成后，内毒素血症小鼠形成更大、血小板含量低的血栓。与内毒素血症WT对照组相比，内毒素血症TLR4小鼠没有增强的血栓形成反应，且循环中的ICAM-1显著降低。与对照组相比，内毒素血症ICAM-1小鼠的血栓明显更小。假设定位于炎症内皮的PMN促进血栓形成，使用抗Ly6G抗体进行PMN清除。矛盾的是，没有PMN形成的VT被放大，这可能与内毒素血症诱导的纤溶酶原激活物抑制剂-1（PAI-1）升高和循环中的因子XIII（FXIII）以及尿激酶型纤溶酶原激活剂（uPA）降低有关。内毒素血症增强的早期VT以TLR-4和ICAM-1依赖的方式发生，并因中性粒细胞减少而增强。抑制ICAM-1和/或TLR-4可能是预防脓毒症相关VT的独特策略。
