Isolation of mouse brain-infiltrating leukocytes for single cell profiling of epitopes and transcriptomes.

High dimensional compositional and transcriptional profiling of heterogeneous brain-infiltrating leukocytes can lead to novel biological and therapeutic discoveries. High-quality single-cell leukocyte preparations are a prerequisite for optimal single cell profiling. Here, we describe a protocol for epitope and RNA-preserving dissociation of adult mouse brains and subsequent leukocyte purification and staining, which is adaptable to homeostatic and pathogenic brains. Leukocyte preparation following this protocol permits exquisite single-cell surface protein and RNA profiling in applications including CyTOF and CITE-seq. For complete details on the use and execution of this protocol, please refer to Guldner et al. (2020) and Golomb et al. (2020).