Which type of glial cells function as resident immune cells in the central nervous system?

Microglia are the resident immune cells in the central nervous system (CNS), playing a crucial role in maintaining homeostasis, responding to injury, and combating pathogens. Unlike other types of glial cells, microglia are derived from yolk sac progenitors and exhibit characteristics similar to macrophages, making them essential for immune surveillance within the CNS. They can detect disturbances and inflammation, and they respond by activating and proliferating to help clear debris and pathogens, as well as modulating the inflammatory response. Their ability to constantly monitor the environment in the CNS positions them uniquely to respond swiftly to any pathological changes, thus ensuring the overall health of neural tissues.