Fig. 4

Repolarizing the inflammatory profile of microglia using sequential cytokine addition. a “M2a→M1” stimulus paradigm. Microglia were treated with 20 ng/mL IL-4 for 2 h followed by 20 ng/mL IFN-γ + 50 ng/mL TNF-α (I + T) for 22 h. b “M1→M2” stimulus paradigm. Microglia were treated with I + T for 2 h followed by either IL-4 (“M1→M2a”) or 20 ng/mL IL-10 (“M1→M2c”) for 22 h. Data are expressed as mRNA counts in 200 ng total RNA (mean ± SEM, n = 6 individual cultures) and were analyzed by one-way ANOVA with Tukey’s post hoc test. The dashed lines indicate expression levels in unstimulated (control) microglia. (Some lines are too low to see.) The comparisons are as follows: asterisk differences from control microglia, number sign effects of a secondary stimulus on the first stimulus. One symbol p < 0.05, two symbols p < 0.01, three symbols p < 0.001