Fig. 3. Stable hepatocyte transduction following neonatal administration of AAV-HITI improves the phenotype of a mouse model of MPS VI.

a Fluorescence microscopy representative images of TBG-DsRed-, gRNA- and scramble-treated livers of mice sacrificed at post-natal day (p) 15, p30 and p90. C57BL/6J mice were injected at p1-2 with 4 × 10¹³ genome copies/kg of each vector. Sections were stained with DAPI; the white scale bar in the upper right image equals 100 µm. The percentage of DsRed+ hepatocytes is reported inside each image. b Serum arylsulfatase B (ARSB) activity measured in gRNA-treated MPS VI mice is reported. c ARSB activity was measured in liver of gRNA-treated and control affected (AF) MPS VI mice as well as of normal (NR) controls. d Urinary glycosaminoglycans (GAGs) were measured in gRNA-, scramble-treated MPS VI AF mice and in NR controls. Values are reported as percentage of age-matched scramble controls. e Histological representative images of storage in liver, heart muscle and cortical bone of gRNA (n = 4)- and control MPS VI AF (n = 2, except for cortical bone n = 4) mice and of NR (n = 3, except for cortical bone n = 5) controls; the black scale bar in the lower right image equals 25 µm. GAG levels were measured in liver (f), kidney (g) and spleen (h) of gRNA-treated and control MPS VI AF mice as well as in NR controls. i Serum albumin levels were measured at p360 in gRNA-, scramble-treated (NR, n = 2; AF, n = 3) and untreated (UT) mice (NR, n = 7; AF, n = 3). MPS VI mice were injected at p1-2 with 6 × 10¹³ genome copies/kg of each vector. Results are represented as median for each group of treatment (numbers in a and column, f) or as a single measurement for each mouse (dot) and as either mean ± SEM for each group of treatment (numbers in e and column, b–d, g–i). *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001 (a, f, Kruskal–Wallis followed by the Conover’s all-pairs rank comparison test; b–e, h, i, one-way ANOVAs followed by the Tukey post hoc test; g Welch ANOVA followed by the Games Howell test). Further details on statistical analysis, including exact p value, can be found in “Methods” section. Source data are provided as a Source Data file. TBG thyroxine-binding globulin, n number of biologically independent samples.