IL-10-deficient Treg cells prevent colitis. (a) Body weight of Rag1−/− mice given sorted Il10−/− or wild-type (WT) CD4+CD25+ Treg cells, together with CD4+CD45RBhi T cells, or of Rag1−/− mice given CD4+CD45RBhi T cells alone (control; None), presented relative to initial body weight. Data are pooled from two independent experiments with six mice each (error bars, s.d.). (b) Histology scores of sections of the large intestine at 6 weeks after the cell transfer described in a. Each symbol represents an individual mouse; small horizontal lines indicate the mean. NS, not significant. Data are pooled from at least two independent experiments.