P2RX7 and Alzheimer disease: Up-regulated expression of P2X7 has been observed in several neurodegenerative diseases: e.g., in astrocytes and microglia in AD (McLarnon et al., 2006; Martin et al., 2019), in microglia from spinal cord of MS and ALS (Yiangou et al., 2006), in astrocytes in MS (Narcisse et al., 2005; Amadio et al., 2017), in the optic nerve of MS patients (Matute et al., 2007) and in the neocortex and hippocampus of patients with epilepsy (Barros-Barbosa et al., 2016; Jimenez-Pacheco et al., 2016).