Protocol for in vitro phagocytosis assay for primary mouse microglia and human embryonic stem cell-derived microglia

Microglia, the resident immune cells of the brain, maintain brain health by clearing detrimental debris, including amyloid-β (Aβ). Here, we present a protocol for assessing Aβ uptake by primary mouse microglia and human embryonic stem cell-derived microglia using an in vitro phagocytosis assay. We describe procedures for pHrodo-labeled oligomeric Aβ treatment and real-time signal detection using the Incucyte SX5 system. We also detail steps for microglia culture, Aβ labeling, and quantification of phagocytosis over time. For complete details on the use and execution of this protocol, please refer to Zhu et al.¹.