Apoptotic thymocytes were induced by incubating with 1μM of staurosproine for 4 h and added into macrophage culture at a ratio as indicated in the figure panels: A, 1:0; B, 1:1; C, 1:2; D, 1:4; E, 1:6; F, 1:8; G, 1:10; H, 1:12. Data were acquired with a flow cytometer. Percentage of phagocytic macrophages was analyzed using the software associated with the flow cytometer.