Fig. 4.
Opsonization of rhMAGE-A3 results in increased DC-uptake levels, significantly mediated by FcγR. a Expression of FcγR of immature DCs. Bars indicate mean ± SEM of n = 62 independent experiments of 54 different donors. Significant differences within indicated receptors were calculated using Friedman test with Dunn’s multiple comparison test, *p < 0.05, **p < 0.01, ***p < 0.001. b Immature DCs (CD11c+) were loaded in parallel with three different rhMAGE-A3-FITC antigen formulation for 30 min. CD11c+/FITC double-positive cells were measured by digital imaging system Scan^R and blotted on the y-axis; FcγR uptake was neutralized by specific antibody, macropinocytosis was inhibited by rottlerin. Data represent relative DC-uptake compared to the unloaded rhMAGE-A3 protein uptake (100 %) of 7 independent experiments; mean ± SEM; paired t-test. Left rhMAGE-A3 protein; middle rhMAGE-A3 opsonized with anti-MAGE monoclonal antibody 6C1; right rhMAGE-A3 opsonized with anti-MAGE antibody and cross-linked with anti-light chain F(ab)2 (IC immune complex). c Immature DCs (CD11c+) were loaded with rhMAGE-A3 opsonized with either unmodified or deglycosylated 6C1 IgG2a antibody. Data represent relative DC-uptake compared to unloaded rhMAGE-A3 protein uptake (100 %) of 5 independent experiments; mean ± SEM; paired t-test