Figure 4. HMGB1 mediates activation of p38 MAPK through TLR2 and TLR4 signalings in KCs from burn rats.

After harvested from burn rats, KCs were pre-incubated with anti-TLR2 or anti-TLR4 antibody prior to HMGB1 administration (100 ng/ml, 48 h). Cytosolic extracts were immunoblotted with phospho-p38 and p38 antibodies. The HMGB1-mediated p38 MAPK activation was significantly blocked by pre-incubation with anti-TLR2 or anti-TLR4 antibody in KCs of burn rats. (A) A representative result. (B) Results from the independent experiments. The p38 activity was expressed as relative densitometry of p-p38/p38. Results were given as mean±SEM (n = 8). After burn injury, the KCs treated with medium or HMGB1 alone were used as unstimulated or positive control respectively. ** = p<0.01 vs. unstimulated controls, ANOVA; ^## = p<0.01, vs. positive controls, ANOVA.