Characterisation of microglia isolated from adult human and rat brain.

A method has been developed to isolate microglia from adult human and rat brain cell suspensions by rosette formation via Fc receptors. Immunocytochemical characterisation of the cells immediately following isolation and after 7-10 days in vitro with a panel of monoclonal antibodies has demonstrated that microglia from adult brain have the phenotypic characteristics and phagocytic capacity of mononuclear phagocytes, but lack the hydrolytic enzyme, non-specific esterase. The ability to isolate rapidly a purified population of microglia from adult brain provides a means for investigating mechanisms of activation and differentiation of tissue macrophages, which could elucidate their role in inflammation of the central nervous system.