Cell-Intrinsic NF-κB Activation Is Critical for the Development of Natural Regulatory T Cells in Mice
Figure 2
IL-2 can only partially rescue Treg cell numbers in the thymus of IκBα-SR Tg mice.
(A) Thymocytes from wild-type (WT) and IκBα-“SuperRepressor” transgenic (IkB-SR Tg) mice were either left untreated (−) or stimulated (+) with PMA and ionomycin for 24 h. The IL-2 concentrations in the supernatants were determined by ELISA. IL-2 secretion from unstimulated cells was below the detection limit. Mean values and SD were calculated from triplicates. Student's t test was used for statistical analyses. *, p≤0.05. (B, C, D) Wild-type and IkB-SR Tg mice were injected either with IL-2 or PBS every 8 h for 2 days and thymi were analyzed by flow cytometry. (B) Representative dot plots from one of three independent experiments are shown. Numbers in the quadrants represent the percentages of cells among CD4SP thymocytes from untreated (PBS) and IL-2 treated mice. (C) Percentages of CD25+Foxp3− cytokine-responsive Treg precursor cells among CD4SP thymocytes, as well as their absolute numbers in the thymus. (D) Percentages of CD25+Foxp3+ mature Treg cells among CD4SP thymocytes, as well as their absolute numbers. (B, C, D) Data were compiled from two independent experiments with three mice per genotype and treatment in each experiment. Each symbol represents an individual mouse. Horizontal bars represent the mean. Mann-Whitney U-test was used for statistical analyses. *, p≤0.05; ns, not significant.