Comparison of AAV serotypes in pig retina: sub-retinal injection versus organotypic explant model. Immunohistochemical analysis of GFP expression (green) driven by seven different AAV serotypes. Representative z-stacks of sub-retinally injected (left side labeled “in vivo”) and explanted (right side labeled “explants”) retinas are shown for each of AAV1 (A–A′ vs. B–B′), AAV2 (C–C′ vs. D–D′), AAV4 (E–E′ vs. F–F′), AAV5 (G–G′ vs. H–H′), AAV6 (I–I′ vs. J–J′), AAV8 (K–K′ vs. L–L′), and AAV9 (M–M′ vs. N–N′). DAPI was used to visualize retinal nuclei. Scale bars = 50 μm.