Using standard techniques during mechanical thrombectomy, the Blood and Clot Thrombectomy Registry and Collaboration (BACTRAC) protocol (NCT03153683) isolates intracranial arterial blood distal to the thrombus and proximal systemic blood in the carotid artery. We augmented the current protocol to study leukocyte subpopulations both distal and proximal to the thrombus during human stroke (n = 16 patients), and from patients with cerebrovascular disease (CVD) undergoing angiography for unrelated conditions (e.g. carotid artery stenosis; n = 12 patients). We isolated leukocytes for flow cytometry from small volume (<1 mL) intracranial blood and systemic blood (5–10 mL) to identify adaptive and innate leukocyte populations, in addition to platelets and endothelial cells (ECs). Intracranial blood exhibited significant increases in T cell representation and decreases in myeloid/macrophage representation compared to within-patient carotid artery samples. CD4⁺ T cells and classical dendritic cells were significantly lower than CVD controls and correlated to within-patient edema volume and last known normal. This novel protocol successfully isolates leukocytes from small volume intracranial blood samples of stroke patients at time of mechanical thrombectomy and can be used to confirm preclinical results, as well as identify novel targets for immunotherapies.

在机械血栓切除术期间使用标准技术，血液和凝块血栓切除术注册和协作 (BACTRAC) 协议 (NCT03153683) 分离出远离血栓的颅内动脉血和颈动脉中的近端全身血液。我们扩大了目前的方案，以研究人类中风期间血栓远端和近端的白细胞亚群（n = 16 名患者），以及脑血管疾病 (CVD) 患者因无关疾病（例如颈动脉狭窄；n = 12 名患者）接受血管造影）。我们从小体积 (<1 mL) 颅内血液和全身血液 (5-10 mL) 中分离出白细胞用于流式细胞术，以识别除血小板和内皮细胞 (EC) 之外的适应性和先天性白细胞群。与患者颈动脉样本相比，颅内血液的 T 细胞表现显着增加，而骨髓/巨噬细胞表现显着降低。CD4⁺ T 细胞和经典树突状细胞显着低于 CVD 对照，并且与患者内水肿体积和最后已知的正常值相关。这种新的方案在机械取栓时成功地从中风患者的小体积颅内血样中分离出白细胞，可用于确认临床前结果，以及确定免疫疗法的新靶点。