FIG 1.

Relative potencies of Stx subtypes. Vero-d2EGFP cells were challenged with 10-fold serial dilutions of Stx1a (triangles), Stx2a (circles), or Stx2c (squares). The extent of protein synthesis after 18 h of incubation (A) or cell viability after 18 h (B), 36 h (C), and 72 h (D) of incubation was then recorded. Values for toxin-treated cells were expressed as percentages of the maximal signal obtained from unintoxicated control cells. Data represent the means ± standard errors of the means of at least 6 independent experiments with 6 replicate samples per experiment.