GFAP and Alzheimer disease: Building upon our existing data using combined RNA in situ hybridization (RNAscope) and immunofluorescence, we found that the mean number of MAPT (tau) mRNA puncta per astrocyte (defined by positive immunofluorescence for GFAP) (Fig. 2a) and the proportion of astrocytes with puncta (Fig. 2b) did not differ significantly between adult control, AD, PSP, and CBD cases [11].