scRNA-seq

Adult mice (12 weeks) were anesthetized and decapitated, and the brain and small intestine were removed immediately and submerged in ice-cold aCSF and D-HANKS, respectively. Single cells from the brain were harvested using an Adult Brain Dissociation Kit (130–107-677, Miltenyi Biotec, Germany) according to the manufacturer’s instructions. Single cells from the small intestine were obtained by digestion with papain (0.8 U/ml, Sigma, P3125), DNase I (50 U/ml, Coolaber, CD4871), FBS (20 μl/ml, Gibco), collagenase I (31.25 U/ml, Sigma, C0130), and collagenase IV (31.25 U/ml, Sigma, C5138). Single-cell suspensions of freshly isolated cells were then resuspended in PBS containing 0.04% ultrapure BSA. scRNA-seq libraries were prepared using Chromium Single-Cell 3' Reagent Kits v2 (10× Genomics) according to the manufacturer’s instructions. The target cell recovery for each library was 7000. Generated libraries were sequenced on an Illumina HiSeq2500 system (Beijing Institutes of Life Science, Chinese Academy of Science).