Figure 2. PGE₂ + IFNγ- or PGE₂-induced IL-6 release was enhanced under ER stress.

(A) Glial cells were treated with tunicamycin (Tm: 1 μg/mL) for 1 h and then stimulated with prostaglandin E₂ (PGE₂: 15 μM) + interferon γ (IFNγ: 20 ng/mL) for 24 h. IL-6 protein levels were detected by ELISA. ER stress increased PGE₂ + IFNγ-induced IL-6 release. ***P < 0.001 PGE₂ + IFNγv.s. PGE₂ + IFNγ + Tm. n = 5. (B) Glial cells were treated with tunicamycin (Tm: 1 μg/mL) for 1 h and then stimulated with PGE₂ (15 μM) + IFNγ (20 ng/mL) for 4 h. IL-6 mRNA levels were detected by RT-PCR. Tm increased PGE₂ + IFNγ-induced IL-6 expression. ***P < 0.001 PGE₂ + IFNγ v.s. PGE₂ + IFNγ + Tm. n = 7. The GAPDH was analyzed as loading control. Full-length gels are presented in Supplementary Fig S2. Full-length gels for GAPDH are presented in Supplementary Fig S3. (C) Glial cells were treated with tunicamycin (Tm: 1 μg/mL) for 1 h and then stimulated with PGE₂ (15 μM) for 24 h. IL-6 protein levels were detected by ELISA. Tm increased PGE₂-induced IL-6 release. **P < 0.01 PGE₂v.s. PGE₂ + Tm. n = 5. Cropped gels were run under the same experimental conditions.