LRP participates in the enhanced phagocytosis of viable WT neutrophils by uPAR^−/− macrophages. uPAR^−/− macrophages were preincubated without or with 1 μg/mL mouse IgG, anti-LRP antibodies, BSA, or RAP for 30 minutes. The medium was then changed to RPMI plus 5% FBS, and viable WT neutrophils were added for 60 minutes, after which the phagocytic index was determined. **P < .01, compared with the group treated with isotype IgG. ***P < .001, compared with the group treated with BSA.