Figure 6

Erk1/2 and p38 MAPK pathways are involved in TNF-α secretion by HKBA- or L-Omp19-stimulated astrocytes. Astrocytes were incubated with inhibitors of MAPK pathways (PD: inhibitor of Erk1/2; SB: inhibitor of p38) two hours before the beginning and kept throughout the culture with HKBA (10⁸ bacteria/ml), L-Omp19 (1,000 ng/ml) and U-Omp19 (1,000 ng/ml). Culture supernatants were harvested at 48 hours post stimulation to assess the secretion of TNF-α by ELISA. Bars express the mean ± SEM of duplicates. Data shown are from a representative experiment of four performed. NS: non-stimulated astrocytes. ***P < 0.001 versus untreated (minus sign); P < 0.001 versus the treatment with PD or SB alone (black star).