FIG 1.

rHBsAg-specific humoral responses are enhanced and sustained by VacSIM delivery. (A) Kinetic evaluation of rHBsAg-specific IgA, IgM, and IgG antibodies in sera of immunized BALB/c mice (n = 10, pooled from 2 independent experiments) were determined by ELISA. Immunization times are indicated by arrowheads. (B) rHBsAg-specific IgM (top) and IgG (bottom) levels from sera collected 21 days postimmunization. (C) The IgG1:IgG2a ratio was determined at 35 days postimmunization. Statistical differences (*, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001) were determined by two-way ANOVA with Bonferroni posttest.