Figure 1.

Expression Profiles of Selected Genes Relevant to SARS-CoV-2 Brain Entry

In a single nuclear RNA-seq profile of human cortical brain tissue (https://celltypes.brain-map.org) (Hodge et al., 2019), there was no evidence of ACE2 expression in any brain cell type. Basigin (BSG) was prominently expressed in pericytes and endothelial cells, whereas neuropilin-1 (NRP1) was detected in endothelial cells and in several classes of excitatory neurons. Low expression of TMPRSS11A and FURIN was found in neurons, whereas CSTB was moderately expressed in most cell types with the exception of astrocytes and oligodendrocytes and their precursors. Endothelial cells and pericytes also express lymphocyte antigen 6 family member E (LY6E) and the interferon (IFN)-induced transmembrane proteins-1 and 3 (IFITM1, IFITM3), which have been shown to restrict SARS-CoV-2 cell entry (Hachim et al., 2020; Pfaender et al., 2020; Zhao et al., 2020). IFN type I receptors (IFNRA1 and IFNRA2) showed higher expression in endothelial cells than in other cell types. Cell cluster annotations are from (Hodge et al., 2019). CPM, transcript counts per million within the cell cluster; FracCellExpr, fraction of cells in which the transcript is detected.