Fig. 3

TLR agonists up-regulate pro-inflammatory cytokine gene expression in enriched but not in purified rat cortical astrocytes. Enriched or purified (L-LME-treated) astrocytes were challenged with LPS (100 ng/ml), zymosan (10 μg/ml) or poly(I:C) (50 μg/ml) and processed after 6 h for IL-1β, IL-6 and TNF-α mRNA expression by RT-PCR. Data are means ± SEM (n = 3) normalized to GAPDH levels and are representative of three experiments. *p < 0.05 and ***p < 0.001 vs control (‘Ctr’). For L-LME-treated cultures, significant differences between the ‘L-LME’ and ‘L-LME/agonist’ groups were noted only in two cases, as indicated by the bar (*p < 0.05). Qualitatively similar results were obtained after 24 h, although relative mRNA levels were lower