Fig. 7.

Inflammatory responses of macrophages cocultivated with the wild-type strain or the fnbA mutant strain. (A) Activation of NF-κB was analyzed by EMSA. (B) mRNA expression of proinflammatory cytokines TNF-α and IL-6 in mouse inflammatory macrophages. SH1000 or its fnbA mutant in the early exponential growth phase was cocultured with mouse inflammatory macrophages at an MOI of 50. Bacteria left untreated or pretreated with 100 μg/ml Fn were used in the NF-κB activation analysis (A). Fn-pretreated bacteria were used in the proinflammatory cytokine expression analysis (B). After a 30-min cultivation, cells were washed with PBS and treated with 20 μg/ml lysostaphin plus antibiotics for 30 min, and then the nuclear extracts or RNAs were prepared.