B17 Establishing a neural progenitor cell model of huntington’s disease

Abstract

Background There is a need for improved human and mouse cell models of Huntington’s disease. Neural stem cells (NSCs) are a pool of stem cell like progenitors responsible for self-renewal and differentiation in the developing CNS leading to the formation of the mature brain. Aims To generate neural progenitor cell lines from the R6/2 mouse model of HD and to investigate these for HD-related phenotypes. Methods Cell lines have been established from E14.5 R6/2 and wild type mouse embryos and cultured in bespoke culture media with growth factors to expand the population. Progenitor populations have been harvested from distinct cortical and striatal progenitors. NSCs have been successfully maintained in a proliferative state for multiple passages and differentiated into neurons and glia that express proteins indicative of mature cell types. Results Neurons show evidence of synaptophysin expression at junctions between cell neurites suggesting synaptic functionality and the formation of rudimentary neural networks. After 14–28 days of differentiation, induced by removal of growth factors, mutant huntingtin (mHTT) aggregation is detectable in R6/2 cell nuclei recapitulating a phenotype found in the mouse model and by clinical histopathology. Initial aggregation can be detected in cell nuclei from 14 days of differentiation in 5% of cells rising to around 10% after 28 days. Detection of mHTT-aggregated protein was also validated via western blot. Super high resolution cell imaging shows earlier aggregation of mHTT and that this occurs in both the cytoplasm and the nucleus. Conclusions This cell model will be used to explore the misfolding and aggregation of mHTT and how this affects cellular function. We have assessed the utility of these cell lines in screening for approaches to modulation mHTT aggregation. Funding Medical Research Council, CHDI Foundation