Abstract WP430: Endothelial Cell Collection from Ipsilateral Middle Cerebral Artery in Acute Ischemic Stroke

Abstract

Introduction: The cerebrovascular endothelium plays a critical role in the pathogenesis of and response to acute ischemic stroke (AIS). To date, techniques to study its function have relied on animal and in vitro models. A robust method of endothelial cell (EC) capture in patients with AIS at early time points, from within the ischemic region, could greatly advance our understanding of cerebrovascular injury. Method: Patients undergoing thrombectomy for middle cerebral artery occlusion (MCA) within 8 hours of onset were offered enrollment if the pass of their stent-retriever device occurred directly into a distal access catheter in the proximal M1 segment, limiting exposure of the device to only the MCA. After retrieval, ECs adherent to the devices were retrieved and stained for EC (CD31) and leukocyte (CD45) markers. EC identity and yield were confirmed by flow cytometry with simultaneous immuno-fluorescence microscopy. Cultured human ECs were used as positive controls. The EC fraction was defined as CD31 + CD45 - with size and morphological features consistent with the positive controls. Results: ECs from stent-retriever devices (n=3) were collected and pooled. Approximately 8% of the collected cells represented ECs. EC collected from the stent-retrievers demonstrated highly similar shape, morphology and antibody staining patterns compared to the positive controls (Figure). Conclusions: Here we provide the first demonstration of a rapid post-thrombectomy method for reliable harvesting of cerebral ECs in humans. The ability to capture these cells in patients with AIS within hours of symptom onset opens many avenues of exploration for determining the role of ECs in AIS.