CLDN5 and neoplasm: Based on the known annotation of marker genes from the literature, we grouped cells of nine clusters into four cell types: GNP-like tumor cells (expressing Math1 and Grin2b), microglia (expressing Aif1 and Cd68), T cells (expressing Cd3d and Cd3e), and endothelial cells (expressing Cldn5 and Cdh5) (Additional file 1: Figure S6a).