Figure 2.

Immunization with CyaA224LCMV or CyaA224LCMV-E5 induces full protection against a lethal LCMV challenge. On days 0 and 21, BALB/c mice were immunized with 50 μg of wild-type CyaA (w.t.), CyaA224LCMV, or CyaA224LCMV-E5 mixed with 1 mg of alum. Control groups received either PBS or 10⁵ foci of LCMV i.p. On day 28 (A) or on day 63 (B), mice were challenged intracerebrally with 10^1.7 foci of LCMV. Mortality was monitored for 21 days, at which time the mice were sacrificed for analysis of serum levels of anti-LCMV antibodies and the presence of viral antigens in the kidneys. The percent of surviving mice and the number of surviving mice out of the total number of challenged mice are shown for each group.