CsA effects on IFN-γ and IL-6 following experimental BMT. (A) IL-6 levels measured in sera of B6D2F1 recipients who received lethal irradiation doses of either 900 or 1300 cGy on day −1 and transplanted with B6.WT BM and splenic T cells on day 0. Data from 2 combined replicate experiments is shown, n = 10 per group. Day 4 vs 7: ****P < .0001; **P = .003. (B) Sera IL-6 levels over time in B6D2F1 recipients irradiated with 1100 cGy on day −1 and transplanted on day 0 with allo BMT grafts consisting of either WT or IL-6^−/− T cells with B6.WT BM. Data from 2 combined replicate experiments is shown, n = 10 per group. (C) IFN-γ, TNF, or (D) IL-6 levels were measured in sera from B6D2F1 recipients treated with saline or CsA and transplanted with B6.WT BM and splenic T cells. CsA was administered at 50 mg/kg per dose daily for 7 days. Data from 3 to 7 combined replicate experiments is shown, n = 29 to 30 per group (day 4), 37 or 38 per group (day 7), and 11 to 16 per group (day 11). Day 4, saline vs CsA: ****P < .0001, IFN-γ; ***P = .005, IL-6; **P = .007, TNF. Day 7, saline vs CsA: ****P < .0001, IFN-γ and TNF; *P = .01, IL-6. Day 11, *P < .05. (E) Th17 B6.IL-17-eYFP fate map reporter cells were enumerated in spleen and lung harvested on day 7 from B6D2F1 recipients treated with saline or CsA, and transplanted with B6.WT BM and splenic T cells (n = 9 to 13 per group). CsA was administered at 5 or 50 mg/kg per dose daily for 7 days. Data from 3 combined replicate experiments is shown; *P = .04, saline vs CsA.