Early microgliosis precedes neuronal loss and behavioural impairment in mice with a frontotemporal dementia-causing CHMP2B mutation

• Published in: Human molecular genetics Vol. 26; no. 5; pp. 873 - 887
• Main Authors: Clayton, Emma L, Mancuso, Renzo, Nielsen, Troels Tolstrup, Mizielinska, Sarah, Holmes, Holly, Powell, Nicholas, Norona, Frances, Larsen, Jytte Overgaard, Milioto, Carmelo, Wilson, Katherine M, Lythgoe, Mark F, Ourselin, Sebastian, Nielsen, Jörgen E, Johannsen, Peter, Holm, Ida, Collinge, John, Oliver, Peter L, Gomez-Nicola, Diego, Isaacs, Adrian M
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.03.2017
• Subjects: Animals; Clinical Medicine; Dementia - genetics; Disease Models, Animal; Endosomal Sorting Complexes Required for Transport - genetics; Endosomal Sorting Complexes Required for Transport - metabolism; Frontotemporal Dementia - genetics; Frontotemporal Dementia - immunology; Frontotemporal Dementia - pathology; Humans; Klinisk medicin; Medical and Health Sciences; Medicin och hälsovetenskap; Mice; Mice, Transgenic; Mutation; Nerve Tissue Proteins - genetics; Nerve Tissue Proteins - metabolism; Neurologi; Neurology; Neurons - pathology; Neurons - physiology; Tongue Diseases - genetics; Tongue Diseases - metabolism; Tongue Diseases - pathology
• ISSN: 0964-6906; 1460-2083
• DOI: 10.1093/hmg/ddx003

Frontotemporal dementia (FTD)-causing mutations in the CHMP2B gene lead to the generation of mutant C-terminally truncated CHMP2B. We report that transgenic mice expressing endogenous levels of mutant CHMP2B developed late-onset brain volume loss associated with frank neuronal loss and FTD-like changes in social behaviour. These data are the first to show neurodegeneration in mice expressing mutant CHMP2B and indicate that our mouse model is able to recapitulate neurodegenerative changes observed in FTD. Neuroinflammation has been increasingly implicated in neurodegeneration, including FTD. Therefore, we investigated neuroinflammation in our CHMP2B mutant mice. We observed very early microglial proliferation that develops into a clear pro-inflammatory phenotype at late stages. Importantly, we also observed a similar inflammatory profile in CHMP2B patient frontal cortex. Aberrant microglial function has also been implicated in FTD caused by GRN, MAPT and C9orf72 mutations. The presence of early microglial changes in our CHMP2B mutant mice indicates neuroinflammation may be a contributing factor to the neurodegeneration observed in FTD.