Fig. 1.

SLA-SE augments mucosal antibody responses against a parenterally delivered vaccine antigen CfaEB. BALB/c (n = 5 per group, per experiment) were immunized twice on Days 0 and 21 via intramuscular immunization with CfaEB +/− SLA-SE and/or dmLT. Intestinal wash samples were collected on Day 35 and assessed for CfaEB-specific IgG (a), IgG1 (b), IgG2a (c), or IgA (d) by ELISA and log₁₀ transformed. e Functional anti-CFA/I antibody titers from the intestinal wash samples were determined by HAI with human red blood cells using ETEC strain H10407. Horizontal bars are drawn at the mean. The lower limit of detection (LOD) is indicated by the dashed line. Data pooled from two experiments indicated with open and closed symbols, respectively, with similar results. *, **, ***, and **** indicate P < 0.05, 0.01, 0.001, and 0.0001, respectively, as determined by one-way ANOVA using Tukey’s multiple comparisons test. All other pairwise comparisons between the groups were not significantly different