Figure 4.

IgE Induction in Germ-free Mice Is Dependent on CD4⁺ T Cells

(A) Germ-free mice were left untreated (n = 5; gray circles) or were depleted of CD4⁺ cells by intraperitoneal injection of anti-CD4 mAb (n = 6; black circles) two times per week starting on the day of weaning until the end of the experiment. IgE levels were measured at the start (28-days-old) and the end (96-days-old) of the experiment. Representative data from two independent experiments is shown.

(B) Total serum IgE levels were measured in germ-free (n = 16; gray circles) and SPF (n = 8; black circles) TCRβδ^−/− mice.

(A and B) Each point represents an individual mouse, and the horizontal dotted line marks the lower limit of detection of the IgE ELISA assay (0.8 ng/ml). ^∗∗p ≤ 0.01; n.s, not significant. p > 0.05 with an unpaired Student’s t test in (A).