Figure 1: Murine exon-6-lacking-IL-15 isoform was generated by alternative splicing in activated immune cells.

(a) Splenocytes were cultured with or without LPS (10 μg/ml) for 24 h. Total RNA extracted from the splenocytes was reverse transcribed into cDNA and amplified by PCR using a specific primer for coding sequences of murine IL-15 cDNA. (b) Coding sequence comparison between IL-15ΔE6 isoform and IL-15. Boxes represent exons and the dashed lines indicate the consequence of alternative splicing. (c) Primary B cells, macrophages, SP2/0 cell line and Raw 246.7 cell line were cultured with or without LPS (10 μg/ml) for 24 h. Total RNA was extracted from these cells and reverse transcribed into cDNA and amplified by PCR. (d) Splenocytes were cultured with or without LPS (10 μg/ml) for 24 h. During LPS stimulation, CHX (1 μg/ml) was added for the last 12 h of culture. The cellular lysates were blotted with rabbit anti-mouse-IL-15 polyclonal Ab followed by goat- anti-rabbit IgG Ab. The data shown represent at least three independent experiments.