Stimulation of mixed glia with TLR2 and TLR7 agonists increases TNFα and promotes preOL cytotoxicity. Rat mixed glial cultures were treated with vehicle (sterile PBS; 5 μl/ml), TLR1/2 agonist Pam3CSK4 (1.0 μg/ml), TLR3 agonist poly(I:C) (50 μg/ml), TLR4 agonist LPS (1.0 μg/ml) or TLR7/8 agonist R848 (5.0 μg/ml) for 48 h. PreOL viability was determined by counting O4+ cells. Scale bar, 50 μm. Results are combined means ± SEM from 4 independent experiments. *, p < 0.05, **, p < 0.01, ***, p < 0.001.