Figure 3. Passive protection of rabbits using convalescent sera against IV challenge with the VollumΔpagΔcyaΔlef mutant.
A. 20 ml of sterile convalescent or control sera were administered IV to rabbits (n = 4) three hours before an IV challenge with 5×106 CFU of the vegetative VollumΔpagΔcyaΔlef mutant cells. B. Cellular antigens recognized by the protective sera. Proteins were extracted by boiling of different encapsulated B. anthracis mutants. The blots were immune-blotted by a representative protective serum. 1. VollumΔpXO1. 2. VollumΔpagΔcyaΔlef. 3. VollumΔpagΔcyaΔlefΔatxA. 4. VollumΔpagΔcyaΔlefΔbslA. The size marker in kDa is marked on the left. The arrowhead marks the location of the BslA protein.