Localization of IgG fluorescent microspheres in vivo after Ad-mediated FcγRIIA cDNA gene transfer. Sprague Dawley rats received Ad FcγRIIA or AdNull intravenously (10⁹ pfu). After 48 hours, IgG fluorescent microspheres (6 × 1012particles) were injected intravenously, and 1 hour later the livers were removed and frozen section were prepared and analyzed by fluorescence microscopy. (A) Naive control; (B) AdNull-infected; and (C) Ad FcγRIIA-infected. Bar = 50 μm.