Fig. 3

Co-culture system of astrocyte-mediated neurotoxicity. We cultured brainstem/spinal cord motor neurons and astrocytes from the same region in parallel (A). We plated FACS sorted motor neurons (B) on top of cytokine stimulated reactive astrocytes (A). Following co-culture, motor neuron survival decreased distinctly when motor neurons were cultured on top of reactive compared with quiescent astrocytes (C, D). Whereas there was a trend for decreased overall neuronal survival (E), motor neurons significantly decreased (F-G). Moreover, among surviving and dying motor neurons, both neurite (H-J), and neuron morphology (K-L), altered. Significance level: NS, non-significant; *, p ≤ 0.05; **, p ≤ 0.01, ***, p < 0.001. Abbreviations: DAPI, 4’,6-diamidino-2-phenylindole dihydrochloride; FACS, fluorescence activated cell sorting; GFP, green fluorescent protein; Hb9, homeobox Hb9; IL-1α, interleukin 1α; MN, motor neuron; sc, spinal cord/brainstem; SSC-A, side scatter; TNF-α, tumor necrosis factor α. Scale bars: C, 100 μm, D, 25 μm