Figure 4
The absence of interleukin-22 (IL-22) in donor cells and type I IFN receptor (IFNAR) in recipient mice decreases graft-versus-host disease (GVHD) severity in a minor histocompatibility antigen-mismatched GVHD model. (a–g) Lethally irradiated wild type (WT) or IFNAR deficient (IFNAR−/−) 129 recipients were transplanted with 5 × 106 B6 WT or IL-22 deficient (IL-22−/−) bone marrow (BM) only or with 10 × 106 B6.WT splenocytes or 10 × 106 B6.IL-22−/− splenocytes (n=5 per group and five independent experiments). (b,c) WT or IFNAR−/− 129sv mice transplanted with BM only, WT graft or IL-22−/− graft were challenged with oral gavage of fluorescein isothiocyanate (FITC)–dextran at day 8 (b) and 20 after allogeneic hematopoietic cell transplantation (allo-HCT) (c). Graph shows plasma FITC–dextran concentrations. Data are combined from at least four independent experiments (n=12). (d,e) Pathology scores in the colon of recipient mice 20 days after allo-HCT. (d) Data are presented as the mean±s.e.m. from cumulative results from four experiments. (e) A representative example of the section of the large intestine of 129sv mice, WT or IFNAR−/−, transplanted with BM only or B6.WT cells or B6.IL-22−/− cells at day 20 ( × 200 magnification). (f) Mean±s.e.m. of percentage of initial weight measured at day 20 after allo-HCT are represented. (g) Survival data are shown (log-rank test, P<0.05 for B6.WT graft in WT 129sv recipients versus B6.IL-22−/− graft in IFNAR−/− 129sv). Data are combined from at least five independent experiments (n=20).
