IL-7 Induces an Epitope Masking of γc Protein in IL-7 Receptor Signaling Complex

Figure 2

IL-7 specific and IL-7Rα dependent reduction of γc surface expression. (a) T cells were stimulated with γc cytokines (IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21) or representative non-γc cytokine (IL-6) as negative control for 10 or 120 minutes, and the γc (4G3) expression was analyzed by FACS. The relative γc expression was calculated as the ΔMFI associated with the cytokine-treated group over the ΔMFI associated with the medium control group. Data are summary of more than three independent experiments (mean and SEM). (b) LN cells were stimulated in the presence or absence of IL-7, and the cytokine receptor expression was analyzed by FACS at the indicated time points. The maximum value of -axis is 250 for 10-minute to 4-hour histograms and is 200 for 16-hour histogram. Histograms are representative of five independent experiments. (c) Thymocytes were stimulated in the presence or absence of IL-7, and the γc (4G3) expression was analyzed 10 and 120 minutes after stimulation by FACS. The cells were gated on CD4⁺CD8⁺ and CD4⁻CD8⁺ thymocytes, and the γc (4G3) and IL-7Rα expression in IL-7 treated cells were compared with IL-7 nontreated thymocytes. The maximum value of -axis is 500 for DP histograms and is 15 for CD8SP histogram. Histograms are representative of three independent experiments. (d) T cells were incubated in the presence or absence of IL-7 for 16 hours, and culture media were changed to fresh media or IL-7 media, and the γc (4G3) expression was analyzed 10 minutes after the media change. The maximum value of -axis is 150 for medium histograms and is 250 for IL-7 pretreated histogram. Histograms are representative of three independent experiments.

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