Lpd–WRC interactions positively regulate phagocytosis, and PtdIns(3,4)P ₂ , Lpd, and VASP localize to the phagocytic cup during CR3-mediated phagocytosis, but PtdIns(3,4)P ₂ is dispensable for CR3-mediated phagocytosis. (A) Representative confocal slice of a RAW 264.7 macrophage expressing the WRC protein Abi1-GFP during phagocytosis and stained with phalloidin. Insets represent the area denoted by the dotted box. Similar results were obtained in three independent experimental repeats. (B) Representative confocal extended-focus projections of RAW 264.7 macrophages expressing Lpd^SWmut (left) and Lpd^SW/EVmut (right) after a 10 min incubation with IgG-opsonized SRBCs. Inside-outside staining was performed to differentiate between internalized/total (red) and non-internalized (blue) SRBCs. (C) Quantification of the phagocytic efficiency in RAW 264.7 macrophages overexpressing either Lpd^WT, Lpd^EVmut, Lpd^SWmut, and Lpd^SW/EVmut. One-way ANOVA of individual phagocytic efficiency values n = 86 (Lpd), n = 80 (Lpd^EVmut), n = 84 (Lpd^SWmut), n = 88 (Lpd^SW/EVmut), across N = 3 independent experiments; data are means ± SEM. (D–F) Representative confocal slices of a RAW 264.7 macrophage expressing GFP-cPHx3 (D), GFP-Lpd (E), and mCitrine-VASP (F) during CR3-mediated phagocytosis. Insets represent the area denoted by the dotted box showing bound SRBCs. Similar results were obtained in three independent experimental repeats. (G) Quantification of the phagocytic efficiency in BFP-INPP4B(C842A)-CAAX (n = 51) and BFP-INPP4B-CAAX–expressing (n = 46) RAW 264.7 macrophages. Unpaired t test of individual phagocytic efficiency values across N = 3 independent experiments; data are mean ± SEM.