FIG 2.

Humoral immune response to Ad5-PAopt in mice. (A to E) Groups of BALB/c mice were intramuscularly or intranasally immunized with 10⁶ or 10⁷ IFU of Ad5-PAopt or intramuscularly injected with 5 μg of rPA, and serum samples were collected at indicated times for detection of IgG (A), IgM (B), IgG1 (C), and IgG2a (D) antibodies and toxin-neutralizing antibodies (E). (F) Dynamic changes of serum neutralizing antibody 2 weeks after intramuscular and intranasal Ad5-PAopt vaccination and intramuscular rPA inoculation. The data are presented as the means ± SEM (n = 6 per group). i.m., intramuscular; i.n., intranasal; rPA+Alum, rPA protein with aluminum adjuvant; IFU, infectious units.