FIGURE 4.

Triptolide pretreatment decreases Mtb HN878-induced expression of IL-6 and Ptgs-2 but posttreatment further increases their expression in MDMs. triptolide pretreatment (A, C): MDMs were pretreated with the indicated concentrations of triptolide for 6 h then infected with Mtb HN878 MOI:2 up to 24 h. DMSO was used as vector control. Total RNA was extracted then IL-6 (A) and Ptgs-2 (C) expression levels were assessed by RT-qPCR. Triptolide post-treatment (B, D): MDMs were infected with Mtb HN878 MOI:2 for 6 h then treated with the indicated concentrations of triptolide up to 24 h. DMSO was used as vector control. Total RNA was extracted then IL-6 (B) and Ptgs-2 (D) expression levels were assessed by RT-qPCR. Relative expression was calculated using the $-\Delta \Delta Ct$ method. *p < 0.05; **p < 0.01; ***p < 0.001.