Role of Microglia in Autism: Recent Advances

The neurobiological basis for autism remains poorly understood. However, the neuroinflammation processes play an important role in the induction of autistic behavioral changes. Microglial cells can exhibit widely differing functions during brain development, including synaptogenesis and stem cell proliferation, in addition to playing a role in the innate immunity. Mounting evidence indicates that microglial activation or dysfunction can profoundly affect neural development, resulting in neurodevelopmental disorders, including autism. These mechanisms in autism have been investigated using neuropathological studies of human autopsy brains, a large number of murine experimental models and in vivo neuroimaging studies of the human brain. The purpose of this review is to discuss microglial activation or dysfunction and to highlight the detrimental role that microglia play in the development of autism. The recent advances presented in this review support that further elucidation of the mechanisms and kinetics of microglial responses will help to establish a window for therapeutic intervention in individuals with autism.

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