FIG. 2.

Comparison of the effects of enterotoxin doses on antigen-specific SW IgA responses after i.g. administration. Shown are means ± SE of anti-A/Beijing8-9/93 HA SW IgA antibody titers of groups of mice immunized with 20-μg doses of A/Beijing8-9/93 HA antigen either alone (HA only) or in combination with enterotoxins as indicated. Asterisks indicate groups whose values are significantly greater than that of the HA only group (P ≤ 0.05). Double asterisks indicate a value that is significantly greater than that of the groups immunized with 10 and 25 μg of wtLT (groups 3 and 4), in addition to that of the HA only group (P ≤ 0.05).