Abstract：
Inflammation including immunothrombosis by neutrophil extracellular traps (NETs) has important implications in acute ischemic stroke and can affect reperfusion status, susceptibility to stroke associated infections (SAI) as well as functional clinical outcome. NETs were shown to be prevalent in stroke thrombi and NET associated markers were found in stroke patients\' blood. However, little is known whether blood derived NET markers reflect the amount of NETs in thrombi. Conclusions from blood derived markers to thrombus composition might open avenues for novel strategies in diagnostic and therapeutic approaches. We prospectively recruited 166 patients with acute ischemic stroke undergoing mechanical thrombectomy between March 2018 and May 2021. Available thrombi (n = 106) were stained for NET markers DNA-histone-1 complexes and myeloperoxidase (MPO). Cell free DNA (cfDNA), deoxyribonuclease (DNase) activity, MPO-histone complexes and a cytokine-panel were measured before thrombectomy and after seven days. Clinical data, including stroke etiology, reperfusion status, SAI and functional outcome after rehabilitation, were collected of all patients. NET markers were present in all thrombi. At onset the median concentration of cfDNA in blood was 0.19 µg/ml increasing to 0.30 µg/ml at 7 days. Median DNase activity at onset was 4.33 pmol/min/ml increasing to 4.96 pmol/min/ml at 7 days. Within thrombi DNA-histone-1 complexes and MPO correlated with each other (ρ = 0.792; p < 0.001). Moreover, our study provides evidence for an association between the amount of NETs and endogenous DNase activity in blood with amounts of NETs in cerebral thrombi. However, these associations need to be confirmed in larger cohorts, to investigate the potential clinical implications for individualized therapeutic and diagnostic approaches in acute ischemic stroke.
摘要：
炎症包括中性粒细胞胞外诱捕网（NETs）引起的免疫血栓在急性缺血性卒中中具有重要意义，并可影响再灌注状态。对卒中相关感染（SAI）的易感性以及功能性临床结局。NETs被证明在卒中血栓中很普遍，并且在卒中患者的血液中发现了与NET相关的标志物。然而,尚不清楚血液来源的NET标记物是否能反映血栓中的NET含量。从血液来源的标志物到血栓组成的结论可能为诊断和治疗方法的新策略开辟了道路。我们前瞻性招募了在2018年3月至2021年5月期间接受机械血栓切除术的166例急性缺血性卒中患者。对可用的血栓(n=106)进行NET标记DNA-组蛋白-1复合物和髓过氧化物酶(MPO)染色。无细胞DNA（cfDNA），脱氧核糖核酸酶（DNase）活性，在血栓切除术前和7天后测量MPO-组蛋白复合物和细胞因子组。临床数据,包括中风的病因,再灌注状态,SAI和康复后的功能结果，收集所有患者。NET标记物存在于所有血栓中。开始时，血液中cfDNA的中位浓度为0.19µg/ml，在7天时增加到0.30µg/ml。开始时的中位DNA酶活性为4.33pmol/min/ml,在第7天增加至4.96pmol/min/ml。在血栓DNA-组蛋白-1复合物中,MPO彼此相关(ρ=0.792;p<0.001)。此外，我们的研究为NETs的数量和血液中内源性DNase活性与脑血栓中NETs的数量之间的关联提供了证据.然而,这些关联需要在更大的队列中得到证实，探讨急性缺血性卒中个体化治疗和诊断方法的潜在临床意义。
