FIG. 4.

Antibodies in immunized mice. Seventeen mice were immunized i.n. with FNZ, SFS, and EAG, 11 of the mice with EtxB and 6 without EtxB. Panel A shows the mean values and standard error of IgA levels against EAG in BAL fluid (P = 0.02). Panel B shows the mean values and standard error of serum dilutions giving an absorbance of 1.0 for the three antigens by an ELISA detecting all classes of antibodies (n = 4 for animals where EtxB was included; n = 3 for animals without EtxB). Panel C shows IgA levels in sera (same animals as described in the legend to 4B) at 40 dilutions. White bars, preimmunization; gray bars, after immunization.