Percent of phagocytosis of biotinylated rhesus monkey E containing bound mouse IgG in the absence (□) or presence (▨) of rabbit antimouse IgG. E contained IgG bound to CR1 (antiCR1 MoAb 7G9, mouse polyclonal anti-CR1 [p@CR1], and SA/p@CR1), or the E were treated with BSA-PBS followed by rabbit antimouse IgG (BSA). The third and fourth bars, respectively, represent biotinylated E treated consecutively with SA and biotinylated MoAb 7G9, or with nonbiotinylated MoAb 7G9 followed by SA and then biotinylated MoAb 7G9. The bar to the right of the dashed line represents the phagocytosis of biotinylated sheep E reacted with SA followed by biotinylated MoAb 7G9. The total number of rabbit antimouse IgG antibodies bound per E were (from left to right): 87, 4,000, 9,200, 5,300, 4,200, 4,300, 1,400.