P2RX7 and tauopathy: Finally, to elucidate the role of the P2RX7-EV axis in tauopathy, we analyzed the microglial transcriptomic response to BDEVs isolated from PS19 and PS19/P2rx7−/−mice following stereotaxic injection into the cortex and hippocampus of 9.5-month-old C57BL/6 mice, followed by FACS-based microglial isolation and bulk RNA sequencing (Fig. 8e).