(A) Opsonization is not required for neutrophil anti-B. anthracis activity. PMA-activated neutrophils were infected with capsule (gray bar)- and toxin (black bar)-producing strains at an MOI of 1:1 in the presence or absence of serum for 30 min.
(B) Neutrophils kill both capsule (gray bar)- and toxin (black bar)-producing B. anthracis independently of NADPH oxidase activity. Activated neutrophils were incubated with DPI (10 μM) before infection. Bacterial counts were determined 30 min post-infection (MOI 1:1).
(C) hNGE kills B. anthracis at low concentrations. Wild-type, toxin-, and capsule-producing strains were incubated with 5%, 7%, and 10% hNGE. After 30 min, remaining CFUs were determined and referred to the number of bacteria in controls of bacteria incubated in buffer. Error bars show SD of three experiments.