What is the primary function of microglia in the central nervous system?

The primary function of microglia in the central nervous system is to act as macrophages. Microglia are specialized immune cells that reside in the brain and spinal cord and play a crucial role in maintaining homeostasis, responding to injury, and defending against pathogens. They are essential for the immune surveillance of the central nervous system, capable of detecting and responding to signs of cellular distress, infection, and injury by phagocytosing (engulfing and destroying) dead cells, debris, and pathogens.

Additionally, microglia contribute to neuroinflammatory responses, which can be protective in nature but may also lead to damage if the response is excessive or inappropriate. Their ability to navigate to areas of injury or infection helps maintain the health of the nervous system by clearing away potentially harmful materials and facilitating repair processes.

In contrast, the other functions mentioned involve different types of glial cells. Neurons are primarily supported by astrocytes, which provide structural support, metabolic assistance, and maintain the blood-brain barrier. Nerve signal transmission is fundamentally the role of neurons themselves, which utilize action potentials and synaptic transmission. Lastly, oligodendrocytes maintain myelin sheaths, which insulate neuronal axons to enhance signal transmission speed. Thus