Figure 3. Absence of host CD70 results in significantly increased pathologic GVHD.

WT or CD70^-/- C57BL/6 mice received 965 cGy irradiation on day -1 and were subsequently transplanted day 0 with 4×10⁶ BALB/c BM + 2×10⁶ PanT. 65 days following allo-HCT mice were sacrificed and small, large intestines, and liver formalin fixed, embedded in paraffin, and stained with hematoxylin and eosin. Samples were scored for GVHD on a scale of 0-4 by a blinded pathologist using an established scoring system (39-41), with mice chosen from one of two individual experiments described in Fig. 2A-B. (A) Scores from all three organs were added to create a combined score. Scores of the (B) large intestine, (C) small intestine, and (D) liver are shown. Each point represents an individual sample and data were analyzed by student's t test. *P<.05. (E) Representative areas of liver tissue (Scale bar 100μm) from WT (left) and CD70^-/- (right) hosts. Arrows indicate damaged bile ducts.