Fig. 2.
Postsymptom antitoxin treatment is fully protective in rabbits intoxicated with BoNT/A, but not in those intoxicated with BoNT/B. Rabbits were exposed to 4 RbIMLD50 of BoNT/A or BoNT/B, and antitoxin (215 IU/kg) was administered intravenously immediately after the onset of spirometry symptoms. Each plotted symbol (o, survival; x, death) refers to an individual animal. The dashed line represents the latest time point (36 h) at which symptomatic rabbits were fully protected by antitoxin treatment. Data were collected from at least three independent experiments. Each experiment included negative control (toxin only) rabbits. TTS values of accompanying negative control (toxin only) rabbits (n=8, 42.25±1.19 h and 41.75±1.32 h for BoNT/A and BoNT/B, respectively) were comparable to those of antitoxin-treated rabbits.