Figure 2: IL-15 modulates the RORγt and Foxp3 expression by CD4+ T cells.
From: IL-15-dependent balance between Foxp3 and RORγt expression impacts inflammatory bowel disease
(a) About 105 RORγt+(Foxp3-) CD4+T lymphocytes from Foxp3-mRFPxRORγt–GFP mice were transferred into RAG2ko or IL-15koRAG2ko mice killed 28 days later: RORγt and Foxp3 expression by CD4+ T cells before (day 0, left panel) and after transfer in the injected RAG2ko and IL-15koRAG2ko mice (day 28, right panel). (b) Percentage among live CD4+ T cells of Foxp3-RORγt+CD4+ T cells (upper panel) and Foxp3+RORγt-CD4+ T cells (lower panel) in RAG2ko or IL-15koRAG2ko recipients. (c) About 105 Foxp3+RORγt+CD4+T cells from Foxp3-mRFP × RORγt–GFP mice were transferred into RAG2ko or IL-15koRAG2ko mice killed 50 days later: RORγt and Foxp3 expression by CD4+ T cells before (day 0, left panel) and after transfer in RAG2ko or IL-15koRAG2ko hosts (right panel). (d) Frequency among live CD4+ T cells of Foxp3-RORγt+CD4+ T cells (upper panel) and Foxp3+RORγt-CD4+ T cells (lower panel) after transfer. (b–d) Data compiled from two separate experiments with at least two mice per group. Black circles represent IL-15koRAG2ko hosts, open circles RAG2ko hosts. (e) Naive CD4+ T lymphocytes from IL-15ko (black circles) or B6 mice (open circles) were cultured 4 days in vitro under Th17-polarizing conditions: percentage among live CD4+ T cells (left) and mean fluorescence intensity (MFI, right) of RORγt-expressing CD4+ T cells in the culture. (f) Naive CD4+ T lymphocytes from IL-15ko mice were cultured like in e in presence or absence of recombinant IL-15: concentration of IL-17 measured by ELISA in cell culture supernatants. (e,f) Data compiled from two separate experiments with at least three mice per group. Each symbol represents an individual mouse. All graphs indicate means; error bars denote s.e.m.; Student’s t-test values: *P<0.05; **0.01<P<0.05; ***P<0.001).
