Is the neuroinflammation observed in autism similar to encephalitis or meningitis ?
NO. In meningitis and encephalitis, the most prominent immune reaction is one of adaptive immunity, the main feature being infiltration of the CNS by inflammatory cells such as T lymphocytes and B lymphocytes along with the production of antibodies. There is also activation of astroglia and microglia in meningitis and encephalitis, but the dominant immune reaction is due to adaptive immunity. In contrast, in autism, there is NO evidence of lymphocyte infiltration or antibody mediated reactions; the most prominent immune response is characterized by activation of microglia and astrocytes, features that characterize innate immune responses within the CNS. These observations suggest that the adaptive immune system does not play a significant pathogenic role in this disorder, at least not during its chronic phase, and that the main immune mechanism involves predominantly innate immune reactions. Since our study focused on autopsy tissues, we cannot exclude the possibility that specific imm
