Figure 1.
In vitro and in vivo toxicity of mutant TcdB. (A) CHO-K1 cells were treated with TcdB wild-type or mutants and cell viability was measured by fluorescence of cells treated with cell viability reagent (PrestoBlue). (B) CD1 mice were challenged IP with either LD100 of toxins (5 μg kg−1 mouse) or 100× LD100 of L1106K (0.5 g kg−1 mouse). Mouse survival was monitored and data were analyzed by Kaplan–Meier survival curve with Log-rank test of significance. (n = 5, P < 0.0001, between wild-type and mutant toxin groups).