protocol was amended: a positive pool serum derived from PE/ alum sensitized mice was used as reference value to calculate Arbitrary Units (AU). Levels of IgG2c were depicted as OD at 405 nm. In addition, serum was collected within 45 minutes after oral challenge and 3 hours after i.p. challenge on day 35, and MMCP-I was determined using a specific ELISA kit according to instructions of the manufacturer (Moredun Scientific, Scotland). Cell culture and cytokine measurement Spleen and MLN single cell suspensions (2.56106/ml) were incubated in the presence or absence of PE (200 mg/ml) for 96 h at 37uC in complete RPMI1640 with 10% FCS, after which culture supernatants were harvested and stored at 220uC until analysis, as described before [14]. Levels of IFN-c, IL-4, IL-5 and IL-13 in culture supernatants were determined by sandwich ELISA according to the instructions of the manufacturers (eBioscience, Austria). Statistical analysis Data are presented as means 6 standard error of the mean (SEM) and analyzed using GraphPad Prism software. Antibody, MMCP-I and cytokine levels and data on ear swelling were logarithmic transformed followed by a one-way ANOVA and Bonferroni as a post-hoc test. Temperature curves were statistically analyzed using a repeated measures ANOVA and clinical scores were statistically analyzed by the Kruskall-Wallis test. Supporting Information Figure S1 Number of platelets, basophils, macrophages and neutrophils in control and depleted mice. (A) Number of platelets in blood of control and mice treated with a rabbit anti- mouse platelet serum. The number of platelets was performed by whole blood analysis on a hematology analyzer. Data are represented as mean 6 SEM of 4 mice. # p,0.001 compared to untreated C3H or C57BL/6 mice. (B) Number of basophils in spleens of control and mice treated with BA103, a basophil depetion antibody. 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