There are no A1 and A2 astrocytes in brain

Objectives: The subsets of astrocytes in the brain have not been fully elucidated. Using bulk RNA sequencing, reactive astrocytes were divided into A1 versus A2. However, using single-cell RNAseq (ScRNAseq), astrocytes were divided into over two subsets. Our aim was to set up the correspondence between the fluorescent-activated cell sorting (FACS)-bulk RNAseq and ScRNAseq data. Results We found that most of reactive astrocytes (RAs) marker genes were expressed in endothelial cells but not in astrocytes, suggesting those marker genes are not suitable for astrocytic activation. The absence of A1 and A2 astrocytes in the brain.