Figure 7.

Effects of inhibitors on viability of PR230 TEM8-T4 and PR230 CMG2-C4 cells treated with PA and LF. Protective effects by NCGC00084148-01 (listed as 148-01) (1), diphyllin (2) and niclosamide (3) and GF 109203 mirror the heptamer formation results by protecting PR230 CMG2-C4 cells, but not PR230 TEM8-T4 cells, indicating a mechanism of action that blocks late-stage vacuolar release but not early stage vacuolar release of LF complex. The cells were pre-incubated with drugs for 30 min, then 100 ng/ml PA + 100 ng/ml FP59 (final concentration) were added and incubated for 3 h. After that the toxin/durg-containing media were replaced with regular growth media containing 10 mM of ammonium chloride and incubated for 48 h as described in Section 4.5.