PAMs are yolk sac-derived microglia that regulate myelinogenesis. They exhibit plasticity, transitioning from a reactive state to homeostasis, then switching to DAM or WAM states during injury or aging. Epigenomic profiling identifies specific enhancers and TFs like ATF4 as key regulators.

References:

• Hamagami N, Kapadia D, Barclay K M, et al. State-specific enhancer landscapes govern microglial plasticity[J]. Immunity, 2026.