Attenuated Severity of GVHD induced by T cells from <i>Rras</i>^−/− animals.

<p>Balb/c mice were given 900 rad lethal dose irradiation and received 5 × 10⁶ of bone marrow cells from WT C57BL/6 mice. These animals were also transfused without (▲) or with splenocytes that were adjusted to include 1 × 10⁶ of T cells from either WT (●) or <i>Rras</i>^−/− (○) C57BL/6 animals on the second day. Body weight changes (A) and animal survival (B) were monitored. Body weight loss data from a representative experiment is shown (A). <i>Bars</i>, SD. One-way ANOVA. **<i>p</i><0.005, ***<i>p</i><0.0001. Survival data are presented by combining two independent experiments with 13 mice per group. Statistical analysis was performed using two-way ANOVA (A) and Log-rank (Mantel-Cox) test (B). ***<i>p</i><0.0001. (C) Hematoxylin and eosin staining of ileal intestines collected on day 21 after T cell transfusion. Upper panels (2.5× <i>Bars</i>, 200 μm); lower panels (20× <i>Bars</i>, 25 μm). (D) Images were analyzed for the number of crypts per field of view. Approximately 30 fields were analyzed from three mice per group. <i>Bars</i>, mean. Unpaired <i>t</i>-test. *<i>p</i>< 0.05.