a, Detection of hF9 mRNA (red) in liver sections using RNAScope in situ hybridization. Liver sections of mice from non-injected, PBS-treated, and Flu-treated groups at the end of experiment in Fig. 2 (60 days after rAAV transduction, ~12 weeks of age) were used for hybridization and counterstained with hematoxylin. Representative images from each injected group are shown. b. Representative images of RNAScope in situ hybridization are provided. In the first two columns, mAlb mRNA was stained in a non-injected normal mouse to determine the albumin locus expression characteristics. Specificity for RNA was confirmed by digestion of tissue with RNAseA. c, Additional images of hF9 mRNA staining in mice injected with Alb-P2A-hF9 vector, with or without fludarabine treatment are shown at various levels of magnification.