Fig. 1

Self-extracellular RNA/Pam2CSK4 complex promotes pro-inflammatory gene expression in astrocytes through TLR2. a, b Primary astrocytes isolated from brains of neonatal mice were treated for 8 h with either 100 pg/ml Pam2CSK4, 1 µg/ml eRNA or Pam2CSK4/eRNA molecule complexes, prepared by co-incubation of 100 pg/µl Pam2CSK4 and 1 µg/µl RNA for 2 h at 37 °C. c, d Astrocytes were treated for 4 h with 1 µg/ml MAb-mTLR2 prior to stimulation with Pam2CSK4/eRNA molecule complexes for 8 h. Untreated cells served as control. a, c Real-time RT-PCR was used to determine transcript levels of pro-inflammatory cytokines. Values are normalized to Rps12 (n = 3–4 per group; One-way ANOVA with Holm–Sidak's multiple comparisons test; * p < 0.05, ** p < 0.01, *** p < 0.001). b, d TNF-α and IL-6 protein levels in cellular supernatants were quantified by ELISA (n = 3–4 per group; One-way ANOVA with Holm–Sidak's multiple comparisons test; * p < 0.05, ** p < 0.01, *** p < 0.001)