Phagocytosis of red cells by macrophages is inhibited by β2 integrin and ICAM-4 antibodies. (A) Effect of mAbs against the CD11a (TS1/22), CD11b (MEM170), CD11c (3.9), CD18 (2E7), and ICAM-4 (1A1) on erythrophagocytosis. The results are presented as relative phagocytosis derived from mean values of the data; ***P < .001, **P < .01.