Journal: Cell reports
Article Title: Inhibitory affinity modulation of FcγRIIA ligand binding by glycosphingolipids by inside-out signaling
doi: 10.1016/j.celrep.2021.109142
Figure Lengend Snippet: (A) DMF-differentiated HL60 cells expressing FcγRIIA (HL60–2A) were treated with vehicle or C24, dextran or β-glucan, and isotype or functional blocking FcγRIIA antibody (IV.3) as indicated. Cells were seeded on immobilized BSA-anti-BSA under static conditions and stained with phalloidin. The area of spread cells and representative images are shown. (B) DMF-differentiated HL60, HL60–2A with scRNA, Lyn shRNA-1 (Lyn-1), or Lyn shRNA-2 (Lyn-2) were evaluated as in (A). (C–E) Human neutrophils (C), HL60–2A cells (D) pretreated with C24 and β-glucan, or HL60–2A cells with indicated shRNAs (E) were treated with IV.3 followed with luminol and anti-mouse F(ab’) to induce cross-linking (XL), and ROS generation (relative light units [RLUs]) was monitored over time. Representative plots (left) and the peak level of ROS (right) for each condition that was normalized to the average of the F(ab’) untreated control are shown. (F) HL60 cells expressing wild-type FcγRIIA (WT) or FcγRIIA ΔITAM mutant were treated with LacCer C24 and β-glucan, dextran, IV.3, or isotype control as indicated and incubated with IgG-opsonized fluorescein isothiocyanate (FITC)-latex beads. Phagocytic index (percentage of FITC-positive cells over total cells) analyzed by FACS is shown. Bar graphs represent fold change compared to vehicle + dextran for (A), native for (B), and WT + dextran for (F). Dotted line represents the value of untreated HL60 for (A), (B), and (F) and no F(ab’) control for (C), (D), and (E). Data are average ± SEM, and individual values are plotted. *p < 0.05 using the Kruskal-Wallis test.
Article Snippet: SA-coated RBCs were then incubated with 20 μg/mL biotinylated human IgG1 (Novus Biologicals, NBP1–96855) for 1 hr at 15°C while shaking.
Techniques: Expressing, Functional Assay, Blocking Assay, Staining, shRNA, Control, Mutagenesis, Incubation