Immune Signaling in neural development, synaptic plasticity and disease

Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, Pacific Hall 1212A, 9500 Gilman Drive, La Jolla, California, USA.
Nature reviews Neuroscience (Impact Factor: 31.43). 08/2004; 5(7):521-31. DOI: 10.1038/nrn1428
Source: PubMed


Research has long supported the view that the brain is immunologically privileged, in part because normal, uninfected neurons were not thought to express major histocompatibility complex (MHC) class I molecules. Recently, however, it has been shown that neurons normally express MHC class I molecules in vivo. Furthermore, accumulating evidence indicates that neuronal MHC class I does not simply function in an immune capacity, but is also crucial for normal brain development, neuronal differentiation, synaptic plasticity and even behaviour. These findings point to new directions for research, and imply that immune proteins could be involved in the origin and expression of neurological disorders.

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Available from: Lisa M Boulanger,
    • "Furthermore, given that MHC class proteins are expressed on neurons, as well as microglia (Boulanger & Shatz, 2004), immune system markers capable of identifying neurons could determine potentially shared mechanisms between central nervous and immune system pathways, which may have implications for the proposed inflammatory hypothesis of schizophrenia. In particular, schizophrenia may not be primarily a disorder of inflammation but arise from disturbances of overlapping downstream molecular pathways, common to both immune and central nervous systems. "
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    • "Cytokines are proteins involved in the activation, coordination and suppression of immune responses. Their neuromodulatory actions appear to be critical for the regulation of neuroplasticity, cell resilience and apoptosis (Boulanger and Shatz, 2004; Golan et al., 2004; Bauer et al., 2007). Macrophages are activated during innate immune response in two functional distinct states (M1 and M2), producing different cytokines. "
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