Figure 1.

Protease active papain induces IgE secretion independent of TLR2, TLR4 or MyD88 signaling. Serum IgE levels immediately before primary immunization (day 0), before secondary immunization (day 14) and at day 21 in Balb/c (a) or C57BL/6 (b) mice are shown. (c) Total IgE response to heat inactivated papain in Balb/c mice, in TLR2/4 -/- mice (d), or MyD88 -/- mice (e). (f) Antigen specific IgE response in mast cell (MC) deficient (Kit^W/W-v) and littermate controls (WT). For each timepoint, n=5-10 (a-c), or n=3-5 (d-f). Data are representative of at least three separate experiments, panels d and e represent data combined from separate experiments. Error bars represent s.e.m.; p values are calculated via the Student's t test, and represent comparisons to HSA immunizations at the indicated time-points; ***, p≤0.0001; **, p≤0.001, *, p≤0.01. If not indicated p>0.05.