Figure 1.

A Dual Reporter Mouse to Quantify AAV Transduction in Satellite Cells

(A) Schematic illustration of the dual reporter mouse harboring a knock-in nuclear GFP (nGFP) at the Pax7 locus and CAG-LSL-tdTomato at the Rosa26 locus. Cre-mediated recombination results in tdTomato expression. (B) FACS plots and controls used for establishing the gating strategy. The green gate identifies Pax7-nGFP⁺ cells, whereas the yellow gate identifies Pax7nGFP⁺/tdTomato⁺ cells. (C) Recombination efficiency of Pax7-nGFP⁺ cells after local injections of Cre packaged in a panel of AAV serotypes (mean ± SEM, n = 5 mice). (D) Recombination efficiency in Pax7nGFP⁺ cells from various skeletal muscle groups after systemic injections of AAV-Cre (mean ± SEM, n = 5 mice). (E) Representative immunofluorescence staining of a Pax7⁺/tdTomato⁺ cell (yellow arrow) contrasted by a Pax7⁻/tdTomato⁻ nucleus (gray arrow). (F) Systemic injection of AAV9-CMV-Cre in mdx versus wild-type mice demonstrates higher transduction of satellite cells in a dystrophic muscle context (mean ± SEM, n = 5 mice).