FIGURE 6.

RhoGDI and YopO RBD block both FcγR- and CR3-mediated phagocytosis. A, J774A.1 lysates were incubated with GST-RhoGDI immobilized on glutathione-Sepharose beads and resolved by SDS-PAGE and Western blot, probing for Rac, RhoA, and actin. A sample of RhoGDI beads and bead eluates was run in parallel. At least 100 GFP-expressing COS-7 cells were scored per experiment. Results shown are representative of three experiments. B, COS-7 cells were co-transfected with FcγRIIA or CR3 and a GFP-tagged construct, either RhoGDIα, YopO RBD, or GFP alone, challenged with appropriately opsonized sRBC for 30 min and scored for sRBC phagocytosis. Data are expressed relative to the GFP control, arbitrarily set at 100%. Data are mean ± S.E. of at least two independent experiments. * indicates p < 0.05.