DOCK5, but not DOCK2, is required for induction of systemic and cutaneous anaphylaxis. (A) The change of rectal temperature in WT (n = 17), Dock2^−/− (n = 12), and Dock5^−/− (n = 18) mice sensitized with anti-DNP IgE antibody and then challenged 24 h later with DNP-HSA. (B) Serum concentrations of histamine in WT (n = 4), Dock2^−/− (n = 6), and Dock5^−/− (n = 6) mice treated as in A. (C) Ear swelling of WT (n = 9), Dock2^−/− (n = 9), and Dock5^−/− (n = 9) mice sensitized with anti-DNP IgE antibody and then challenged 24 h later by epicutaneous application of DNFB in acetone and olive oil (left ear) or vehicle alone (right ear). Ear swelling was calculated as the difference between the thickness of the left and right ear. (A–C) Data were collected from seven (A), six (B), or three (C) separate experiments and are indicated as mean ± SEM; *, P < 0.05; **, P < 0.01. (D) Histological sections of the right ears (control) and left ears (DNFB) stained with hematoxylin and eosin. Representative data of nine mice per group are shown. (E) Toluidine blue staining of the ear skin and stomach from WT and Dock5^−/− mice. For each tissue, the number of mast cells per square millimeter is compared between WT and Dock5^−/− mice (mean ± SD; n = 3). Bars: (D) 200 µm; (E) 100 µm. (F) Flow cytometric analysis for peritoneal mast cells from WT and Dock5^−/− mice. The numeral in the square indicates the percentage of mast cells for total peritoneal exudate cells. The number of peritoneal mast cells is compared between WT and Dock5^−/− mice (mean ± SD; n = 3). (E and F) Data are representative of two independent experiments.