Oligomer-enriched Aβ has no effect on IL-1β-induced C/EBPδ expression levels in rat primary astro-microglial cultures. A) Representative western blot of Aβ preparations used for cell treatments showing the presence of high levels of fibrillar Aβ only in the fibril-enriched preparation (lane 2) and not in the oligomeric-enriched preparation (lane 1). B) Statistical analysis of Thioflavin T fluorescence in the presence of fibril-enriched Aβ preparation (fAβ; open bar) and oligomer-enriched Aβ preparation (oAβ; filled bar). The data represent mean ± SEM for four independent experiments. A.U., arbitrary units. C) Representative western blot of C/EBPα (p42 and p30) and C/EBPδ in primary astro-microglial cultures from rat. Cells were exposed to an Aβ preparation mainly consisting of oligomers for 3 h. 20 μg of protein lysate was loaded in each lane. D) Relative abundance of C/EBPα showing decreased protein levels in response to LPS (1 μg/ml), but no effect in response to oligomer-enriched Aβ (10 μM) and/or IL-1β (10 ng/ml). E) Relative abundance of C/EBPδ showing increased protein levels in response to IL-1β or LPS, and no change on response to IL-1β when oligomer-enriched Aβ is present. The data represent mean ± SEM for two cultures derived from three independent experiments. *p < 0.05, **p < 0.01, significantly different as indicated.