Peripheral blood cell counts. Peripheral blood was sampled from each mouse 1 day before and weekly after transfusion until death. Average counts for WBC (A) RBC (B) and PLT (C) were plotted for each week. Error bars represent the standard error for each group. Mice in the GVHD group (squares) developed pancytopenia 2 to 3 weeks after transfusion. Levels of WBC, RBC, and PLT for mice in the control (diamonds), PCT (triangles), and gamma (circles) groups were not statistically different at any time after transfusion (P > .05) when analyzed by Student’s t-test.