Table_1_Quantitative and Correlational Analysis of Brain and Spleen Immune Cellular Responses Following Cerebral Ischemia.docx

Stroke is a multiphasic process, and the initial ischemic phase of neuronal damage is followed by secondary innate and adaptive responses that unfold over days after stroke, offer a longer time frame of intervention, and represent a novel therapeutic target. Therefore, revealing the distinct functions of immune cells in both brain and periphery is important for identification of immunotherapeutic targets for stroke to extend the treatment time window. In this paper an examination of the cellular dynamics of the immune response in the central nervous system (CNS) and periphery provoked by cerebral ischemia is provided. New data is presented for the number of immune cells in brain and spleen of mice during the 7 days following middle cerebral artery occlusion (MCAO). A novel analysis of the correlation among various cell types in the brain and spleen following stroke is presented. It is found that the infiltrated macrophages in the ischemic hemisphere positively correlate with neutrophils which implies their synergic effect in migrating into the brain after stroke onset. It is noted that during infiltration of adaptive immune cells, the number of neutrophils correlate positively with T cells, which suggests neutrophils contribute to T cell infiltration in the stroked brain. Furthermore, the correlation among neurological deficit and various immune cells suggests that microglia and splenic adaptive immune cells (T and B cells) are protective while infiltrating peripheral myeloid cells (macrophage and neutrophils) worsen stroke outcome. Comprehension of such immune responses post cerebral ischemia is crucial for differentiating the drivers of outcomes and also predicting the stroke outcome.

脑卒中是一类多相性病理过程，神经元损伤的初始缺血阶段之后，会继发一系列固有免疫与适应性免疫应答——此类应答在卒中发作后数日内逐步演进，不仅提供了更长的干预时间窗，同时也是全新的治疗靶点。因此，阐明免疫细胞在脑部与外周组织中的独特功能，对于识别脑卒中的免疫治疗靶点、延长治疗时间窗具有重要意义。本研究针对脑缺血诱发的中枢神经系统（central nervous system, CNS）与外周组织的免疫应答细胞动态变化展开了系统分析，提供了小鼠在大脑中动脉闭塞（middle cerebral artery occlusion, MCAO）模型术后7日内，其脑部与脾脏内免疫细胞数量的全新实验数据，并针对卒中发生后脑内与脾脏内各类细胞间的相关性开展了创新性分析。研究发现，缺血侧半球内的浸润巨噬细胞与中性粒细胞呈正相关，这提示二者在卒中发作后向脑部迁移的过程中存在协同效应；此外，在适应性免疫细胞浸润阶段，中性粒细胞数量与T细胞数量呈正相关，这表明中性粒细胞可促进T细胞向卒中受损脑部浸润。进一步分析神经功能缺损与各类免疫细胞间的相关性后可知，小胶质细胞与脾脏来源的适应性免疫细胞（T细胞与B细胞）具有神经保护作用，而浸润的外周髓系细胞（巨噬细胞与中性粒细胞）则会恶化卒中预后。深入理解脑缺血后此类免疫应答机制，对于明确卒中预后的影响因素以及预测卒中预后均至关重要。