Basophil depletion during infection of sensitized 4get/rag^−/− mice. (A) Percentages and total numbers of basophils (left) and eosinophils (right) in the blood, spleen, and lung of anti-Thy1.2 treated (▩) or control (□) 4get/rag^−/− mice that had been sensitized with serum from N brasiliensis–infected wild-type mice and infected with N brasiliensis 10 days before analysis. As control, mice were treated with serum from naive wild-type mice (▨). Plots show combined results from 2 independent experiments with 5 to 6 mice total. *P < .001; **P < .05 by Mann-Whitney U test. (B) Number of mast cells and eosinophils in the peritoneum of sensitized and infected 4get/rag^−/− mice that had been treated with anti-Thy1.2 or not. Each dot represents 1 mouse. (C) Semiquantitative RT-PCR analysis of total lung tissue for Th2-associated cytokines and markers for alternatively activated macrophages. The following samples were compared: naive (noninfected 4get/rag^−/−) mice, infected (day 4 N brasiliensis–infected 4get/rag^−/−) mice, sensitized and infected mice (4get/rag^−/− mice that had been sensitized with serum from N brasiliensis–infected wild-type mice before infection), and sensitized, infected, and anti-Thy1.2 mice (sensitized and infected 4get/rag^−/− mice that were depleted of basophils by anti-Thy1.2 treatment).