Immunogold labeling for gamma chain (and kappa chain, not shown) is positive along the linear junctions of erythroblasts (arrowheads) (a), as well as between glove finger invaginations (b and c), showing that the monoclonal IgG are indeed responsible for the synartesis (Original magnification: [a]: ×55,000; [b]: 55,000; [c]: 45,000).