Modulation of microglial phenotypes by CD200

Abstract

Microglia are the principal immune cells of the CNS continually surveying their micro-environment for endogenous and exogenous stimuli which may threaten the immunological balance. Recent studies have suggested that activated microglia, like macrophages, adopt different phenotypes depending on the stimulus; IFNy induces classical activation of microglia, whereas IL-4 induces an alternative activation state. A deactivation state has been described in which the interaction between ligand-receptor pairs, for example CD200-CD200R, suppress the immune response. The focus of this study was to investigate the modulatory role of CD200 on different microglial phenotypes.