Department of Neurology, Goethe University, Frankfurt, Germany.
Edinger Institute (Institute of Neurology), Goethe University, Frankfurt, Germany.
Nat Protoc. 2023 May;18(5):1510-1542. doi: 10.1038/s41596-023-00805-y. Epub 2023 Mar 1.
The neurovascular unit (NVU), composed of endothelial cells, pericytes, juxtaposed astrocytes and microglia together with neurons, is essential for proper central nervous system functioning. The NVU critically regulates blood-brain barrier (BBB) function, which is impaired in several neurological diseases and is therefore a key therapeutic target. To understand the extent and cellular source of BBB dysfunction, simultaneous isolation and analysis of NVU cells is needed. Here, we describe a protocol for the EPAM-ia method, which is based on flow cytometry for simultaneous isolation and analysis of endothelial cells, pericytes, astrocytes and microglia. This method is based on differential processing of NVU cell types using enzymes, mechanical homogenization and filtration specific for each cell type followed by combining them for immunostaining and fluorescence-activated cell sorting. The gating strategy encompasses cell-type-specific and exclusion markers for contaminating cells to isolate the major NVU cell types. This protocol takes ~6 h for two sets of one or two animals. The isolation part requires experience in animal handling, fresh tissue processing and immunolabeling for flow cytometry. Sorted NVU cells can be used for downstream applications including transcriptomics, proteomics and cell culture. Multiple cell-type analyses using UpSet can then be applied to obtain robust targets from single or multiple NVU cell types in neurological diseases associated with BBB dysfunction. The EPAM-ia method is also amenable to isolation of several other cell types, including cancer cells and immune cells. This protocol is applicable to healthy and pathological tissue from mouse and human sources and to several cell types compared with similar protocols.
神经血管单元 (NVU) 由内皮细胞、周细胞、相邻的星形胶质细胞和小胶质细胞以及神经元组成,是中枢神经系统正常功能所必需的。NVU 对血脑屏障 (BBB) 的功能具有重要的调节作用,而 BBB 在几种神经疾病中受损,因此是一个关键的治疗靶点。为了了解 BBB 功能障碍的程度和细胞来源,需要同时分离和分析 NVU 细胞。这里,我们描述了一种基于 EPAM-ia 方法的方案,该方法基于流式细胞术,可同时分离和分析内皮细胞、周细胞、星形胶质细胞和小胶质细胞。该方法基于使用酶、针对每种细胞类型的机械匀浆和过滤对 NVU 细胞类型进行差异处理,然后将它们组合进行免疫染色和荧光激活细胞分选。门控策略包括细胞类型特异性和排除标记物,用于分离主要的 NVU 细胞类型的污染细胞。该方案需要大约 6 小时来完成一组两个或两组一个或两个动物的实验。分离部分需要具备动物处理、新鲜组织处理和流式细胞术免疫标记方面的经验。分离的 NVU 细胞可用于下游应用,包括转录组学、蛋白质组学和细胞培养。然后可以应用多细胞类型分析 (如 UpSet) 来从与 BBB 功能障碍相关的神经疾病的单个或多个 NVU 细胞类型中获得稳健的靶标。EPAM-ia 方法也适用于分离其他几种细胞类型,包括癌细胞和免疫细胞。该方案适用于来自小鼠和人类来源的健康和病理组织,以及与类似方案相比的几种细胞类型。