Consumption of RBCs by liver and lymph node APCs. Syngeneic RBCs were labeled with DiO and transfused into recipient mice. Twenty-four hours after transfusion, livers and lymph nodes were processed. Macrophages or DCs were visualized by staining with anti-F4/80 or anti-CD11c (not shown) After gating on liver macrophages (A), liver DCs (B), lymph node macrophages (C), or lymph node DCs (D), DiO fluorescence was measured in each populations (–). Untransfused mice were used as a negative control for background DiO fluorescence (------). Staining from representative mice is shown, and y-axes of histograms represent percentages of maximum peak value. This experiment was performed 3 times with similar results.