AGER and neurodegenerative disease: However, the recent scientific approaches, such as single-cell RNA sequencing, have revealed that these glial cells have multiple reactive phenotypes related to their regional location and the type and stage of neurodegenerative diseases they are in ref. 275 Microglia and astrocyte sense stimulus through cellular receptors on the surface (e.g., TLR, RAGE, cGAS), and secrete proinflammatory cytokines, chemokines, lipid mediators, NO and so on, to recruit additional immune cells and remove pathological agents.