Inflammation is a hallmark of neurodegenerative diseases including ALS and FTD. However, whether this process contributes to the onset of these diseases remains unclear. Now, University College London’s Adrian Issacs and colleagues report that a mouse model of CHMP2B FTD exhibits early microglial activation in the brain more than 12 months before the first signs of the disease.
The study, published on January 16 in Human Molecular Genetics, found increased activated microglia in key FTD-affected regions of the brain. What’s more, upon disease onset, these immune cells produced significant levels of the pro-inflammatory cytokines IL1β and TNFα. The symptoms, which occur late and include behavioral and motor deficits, resemble key aspects of the human disease. The CHMP2B form of FTD lacks TDP-43 pathology.
The results suggest that inflammation may occur early in the brain and drive the pathology of CHMP2B-linked disease. The study adds to growing evidence that immune system dysfunction may increase the susceptibility to neurodegenerative diseases (Miller et al., 2016; Miller et al., 2014).
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