Answer:
Microglia are specialized brain cells that act as the first and main form of immune defense in the brain. Microglia can undergo changes in their morphology, phagocytic activity, chemotactic activity, surveying activity, and inflammatory responses that could be relevant to their involvement in disease. Activation of microglia is a hallmark of brain pathology, but chronic activation of microglia may, in turn, cause neuronal damage through the release of potentially cytotoxic molecules such as proinflammatory cytokines, reactive oxygen intermediates, proteinases, and complement proteins.
