FIG. 9.

S. suis activates nuclear factor NF-κB in murine microglial cells. The cells were infected with either the S. suis WT strain or its CPS⁻ mutant (1 × 10⁶ cells) for 0.5 to 12 h. Noninfected cells were used as negative controls. LPS (1 μg/ml) served as a positive control. The cells were lysed, and nuclear extracts were subjected to EMSA. The presence of NF-κB-activated proteins in the cell nuclei was demonstrated by binding to oligonucleotide probes containing a single copy of the NF-κB motif 5′-AGT TGA GGG GAC TTT CCC AGG C-3′ end labeled with [γ-³²P]ATP. The binding reaction mixtures were electrophoresed on native 4% polyacrylamide gels to separate bound and unbound DNA probe. sp, specific probe; nsp, nonspecific probe.