RBC antigen loss and AMIS induction are closely related. C57BL/6 mice were transfused with PKH26⁺HOD-RBC. Twenty-four hours later, mice received AMIS-inducing antibodies (Table 2), with the HEL-specific IgM response assessed on day 7. Mice injected with PBS instead of AMIS-inducing antibodies were used as a positive control for alloimmunization (100%) (orange asterisk). Correlation between AMIS activity and antigen loss induced at (A) 2 hours and (B) 24 hours was determined by Spearman test. The panel of anti-HOD antibodies assessed included anti-HEL pIgG (solid orange triangle), monoclonal 4B7 (open inverted orange triangle), 2F4 (open inverted red triangle), GD7 (open inverted blue triangle), and a blend of monoclonal (4B7 + 2F4) (filled inverted orange triangle), mouse pIgG anti–OVA at 25 μg (open orange circle), and 50 μg (filled orange circle), rabbit pIgG anti–OVA at 10 μg (filled blue diamond), 25 μg (filled red diamond), 50 μg (filled green diamond), and 75 μg (filled orange diamond), and anti-Duffy antibodies CBC-512 (open orange square), deglycosylated CBC-512 (crossed orange square), MIMA29 (open orange diamond), and deglycosylated MIMA29 (crossed orange diamond).