FIG 4.

LtdR regulation influences GBS invasion into the brain endothelium. (A and B) Transmission electron micrographs of hBMEC infected with WT (A) or ΔltdR mutant (B) GBS. (C) Invasion of WT GBS, the ΔltdR mutant, and the complemented strain into hCMEC was quantified after a 2-h infection. (D) Adherence of WT GBS and the ΔltdR mutant strain to hCMEC was assessed after a 30-min incubation. (E) The intracellular survival of WT GBS and the ΔltdR mutant strain relative to that of the WT and the ΔltdR mutant at 2 h postinfection was determined up to 8 h postinfection. Experiments were performed at least 3 times in triplicate, and error bars represent SDs; the results of a representative experiment are shown. *, P < 0.05; **, P < 0.005; n.s., not significant.