Figure 2.
Viability of U937 macrophages (A) and human gingival fibroblasts (B) upon stimulation with T. forsythia ATCC 43037. Cells were stimulated with wild-type T. forsythia (107 cells/mL), T. forsythia ΔtfsAB mutant (107 cells/mL), or P. gingivalis LPS (1 μg/mL) for 24 hrs, and the cell viability was measured in an MTT assay. Each value represents the mean value ± SD of 8 values measured in one representative assay. A similar tendency was also observed in the other viability experiments. *Significantly different from control, with P < 0.01.