Martinez-Vargas Marina, Saini Arun, Pradhan Subhashree, Gardea Luis, Stoll Barbara, Didelija Inka C, Vijayan K Vinod, Nguyen Trung C, Cruz Miguel A
Department of Medicine, Baylor College of Medicine, Houston, TX, USA.
Center for Translational Research On Inflammatory Diseases at the Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX, USA.
Intensive Care Med Exp. 2024 Aug 29;12(1):75. doi: 10.1186/s40635-024-00660-5.
Sepsis can lead to coagulopathy and microvascular thrombosis. Prior studies, including ours, reported an increased level of extracellular vimentin in blood derived from septic patients. Moreover, we identified the contribution of extracellular vimentin to fibrin formation and to the fibrin clot structure ex vivo in plasma from septic patients. Here, we tested the status of plasma vimentin and its impact on fibrin clots using our recently described swine model of methicillin-resistant Staphylococcus aureus (MRSA) sepsis-induced coagulopathy.
We employed ELISA, size-exclusion chromatography, vimentin antibodies, confocal microscopy, and turbidity assays on piglet plasma obtained at pre- and post-MRSA inoculation. Plasma vimentin level at 70 h post-MRSA inoculation was on average twofold higher compared to pre-infection (0 h) level in the same animal. Anti-vimentin antibody effectively reduced fibrin formation ex vivo and increased porosity in the fibrin clot structure generated from septic piglet plasma. In contrast to plasma at 0 h, the size-exclusion chromatography revealed that phosphorylated vimentin was in-complex with fibrinogen in septic piglet plasma.
Thus, our swine model of sepsis-induced coagulopathy, reproduced increased extracellular circulating vimentin and subsequent potentiation of fibrin formation, often observed in septic patient. These outcomes validate the use of large animal models to investigate the dysregulated host immune response to infection leading to coagulopathy, and to develop new therapies for sepsis-induced disseminated microvascular thrombosis.
脓毒症可导致凝血病和微血管血栓形成。包括我们的研究在内，先前的研究报告称，脓毒症患者血液中的细胞外波形蛋白水平升高。此外，我们还确定了细胞外波形蛋白对脓毒症患者血浆中纤维蛋白形成和体外纤维蛋白凝块结构的作用。在此，我们使用最近描述的耐甲氧西林金黄色葡萄球菌（MRSA）脓毒症诱导凝血病的猪模型，测试了血浆波形蛋白的状态及其对纤维蛋白凝块的影响。
我们对MRSA接种前后获得的仔猪血浆进行了酶联免疫吸附测定（ELISA）、尺寸排阻色谱法、波形蛋白抗体检测、共聚焦显微镜检查和浊度测定。与同一动物感染前（0小时）水平相比，MRSA接种后70小时的血浆波形蛋白水平平均高出两倍。抗波形蛋白抗体有效地减少了体外纤维蛋白的形成，并增加了脓毒症仔猪血浆产生的纤维蛋白凝块结构的孔隙率。与0小时的血浆相比，尺寸排阻色谱显示磷酸化波形蛋白在脓毒症仔猪血浆中与纤维蛋白原结合。
因此，我们的脓毒症诱导凝血病猪模型再现了脓毒症患者中常见的细胞外循环波形蛋白增加和随后纤维蛋白形成增强的现象。这些结果验证了使用大型动物模型来研究宿主对感染导致凝血病的免疫反应失调，并开发针对脓毒症诱导的弥漫性微血管血栓形成的新疗法。
