IgE responses after intragastric sensitization. C3H/HeOuJ mice were intragastrically exposed to PBS, (control) PE, or Ara h 1, 2, 3, or 6 and CT during a 4 week period, as described in material and methods. Graphs depict serum levels of PE, Ara h 1, 2, 3, or 6 specific IgE in arbitrary units (AU) at day 36. Data are represented as mean ± SEM of 8 mice. *: p < 0.01 compared to control.