Purified CD19⁺ B cells from healthy donors were pretreated with dexamethasone (10 nM) or left untreated for 24 hours. Cells were treated with the 17-HDHA or RvD1, followed by stimulation with an IgE-inducing cocktail for a certain amount of time for each experiment. (A) B cells were incubated for 6 days, and IgE levels were measured by ELISA. B cells were stimulated for 1 day or 3 days, and ɛGLT RNA levels (B), or mature IgE mRNA levels (C), were measured, respectively, using RT-qPCR. (A–C) Experiments were repeated in 2–7 different donors. Each symbol represents an individual donor and represents means of triplicates. (D) One day after B cells were stimulated, [³H]thymidine (1 μCi/well) was added to the culture and incubated for another 48 hours. Cells were harvested at day 3 after stimulation, and incorporation was measured with Topcount Luminometer. Data shown represent 3 different donors. (E) B cells were stimulated for 6 days when cell culture supernatants were collected and applied to PPRE-luciferase assay. Each sample’s luciferase activity was normalized to untreated cells (no 17-HDHA and no dexamethasone). Data shown are from 2 different donors. Each symbol represents an individual donor and represents means of triplicates. Data were analyzed by repeated-measures 2-way ANOVA with Tukey’s post test, *P ≤ 0.05, **P ≤ 0.01, ^#P ≤ 0.05, ^##P ≤ 0.01, ^###P ≤ 0.001 (pound signs compare values with or without dexamethasone, asterisks compare values with or without 17-HDHA). ɛGLT, ɛ germline transcript; RT-qPCR, reverse transcriptase quantitative PCR; PPRE, PPAR response element.