Figure 1. Hepatic gene transfer of hHer2 by AAV8 delivery and transposase gene editing.

(A) Design of the AAV8 vector, which includes a truncated human Her2 gene (hHer2) and a fluorescent reporter gene (Katushka) that are expressed by the liver-specific thyroid hormone-binding globulin (TBG) promoter. Mice were i.v. injected with AAV8, and their livers were harvested 1 month later. (B) IVIS imaging of fluorescence in ex vivo livers harvested from mice that received either no genomic copies (GCs), 1.5 × 10¹⁰ GCs, or 1.5 × 10¹² GCs of AAV8. (C) Immunohistological assessment of hHer2 expression in mice that received either 0, 1.5 × 10¹⁰, or 1.5 × 10¹² GCs of AAV8. Darker Her2-stained cells have a perivascular pattern (black arrowhead) and are less frequent than the fainter Her2-stained cells (white arrowheads). Scale bars: 400 μm (left) and 200 μm (right). (D) Mean hepatocytes ± SEM were quantified for dark or faint Her2 staining by digitizing the IHC images using ImageScope and then analyzed using Aperio imaging software. Each group contained 4 mice except for 1.5 × 10¹² GC, which had an n of 1. (E) Overview of gene editing using the piggyBac transposase system. The transposon vector contained a fluorescent reporter gene (IRFP720) that was expressed using the liver-specific TBG promoter. (F) Imaging of 6 mouse livers harvested 2 months after injection with the IRFP720 fluorescent reporter plasmid and either with or without the PiggyBac transposase DNA vector. (G) Detection of fluorescent reporter expression by flow cytometry in isolated mouse hepatocytes representative of the livers shown in F.