Cells were cell sorted and mRNA was extracted, reverse transcribed, and measured by real-time PCR. Left is a representative dot plot of each experiment. (A) Tonsil B cells were stained and cell sorted according to their respective IgD⁺, IgD⁻CD44⁻, and IgD⁻CD44⁺ phenotype. Cell-cycle analysis was performed on all 3 sorted populations stained with propidium iodide (PI; note that 52% of IgD⁻CD44⁻ centroblasts are in the S+G2/M phases of the cell cycle). (B) Cells were stained with CD27 and CD38 MAbs. (C) Cells were stained with CD19 and CD5 MAbs. (A-C) Histograms on the right show the relative expression of IL-24 mRNAs in sorted populations by quantitative polymerase chain reaction (qPCR). Mean ± SD from 3 to 6 experiments/cell population, each in duplicate, normalized for control GAPDH.