Donor Th17 plasticity and proinflammatory profile is limited by immunosuppression. (A-D,F-H) Donor CD4⁺ T-cell cytokine expression was examined after allo-SCT (A-B,E-F) WT.B6 → B6D2F1 (G-CSF mobilized grafts) or (C-D) WT.B6 or IL-12p40^−/− BM, WT.B6 T-cells → Balb/c. (A) Representative FACS analysis of splenic CD4⁺ T cells and (B) proportion of CD4⁺IL-17A⁺ T cells coexpressing IFNγ d7 after allo-SCT in the presence or absence of increasing doses of CsA (mean ± SEM, n = 8 mice per group, pooled from 2 independent experiments, ***P < .001). (C) Representative images and (D) quantitative analysis of IL-12p40-YFP⁺ cells in mLN explants at d12 posttransplant, unstained tissues were captured by multiphoton confocal microscopy (20× objective) with spectral detection and linear unmixing (unmixed channels are shown: blue = CFP; yellow = YFP; scale bars = 300 μm). (E) Cytokine production by BMDCs was assessed in response to overnight stimulation in the presence and absence of CsA. Data are expressed as fold change relative to CpG-only stimulation (mean ± SEM, data pooled from 2 independent experiments, ***P < .001). (F) Representative FACS analysis of splenic CD4⁺ T cells, (G) proportion of CD4⁺IL-17A⁺ T cells coexpressing IFNγ, (H) frequency of cytokine-positive CD4⁺ T cells d7 after allo-SCT in the presence or absence of CsA (50 mg/kg) or Rapa (rapamycin) (0.6 μg/kg) (mean ± SEM, n = 6 mice per group, *P < .05, **P < .01, ***P < .001).