Fig. 4
MassARRAY® analysis to evaluate methylation of CpG islands in HBV DNA following hydrodynamic injection of mice. a HBV coordinates encompassing CpG island II (see Fig. 1a) are indicated together with each CpG within the sequence. Methylation status of single CpGs was measured from individual mice using MassARRAY® and percent methylation indicated according to the shading. The Mock group of mice (animals numbered 69 to 72) received pTZ57R DNA instead of plasmid with the rTALE cassettes. CMV SPL (animals numbered 74 to 78), CMV SPR (animals 79 to 83), MTTR SPL (animals 84 to 87) and MTTR SPR (animals 89 to 93) received the SPL or SPR rTALE cassette under control of CMV or MTTR promoters. CpGs highlighted by the shaded box indicate where the methylation in the rTALE-treated animals was approximately 50% more than that of the control group. b Box and whiskers plot showing the percentage of methylation at CpG38 in mice treated with CMV and MTTR rTALEs. A 2-fold increase was observed for CMV-SPL, CMV-SPR and MTTR-SPL, with a maximum of 51% methylation (error bars = SEM, n = 4 for mock and MTTR, n = 5 for CMV). p = 0.0079 for CMV-SPR using one tailed Mann-Whitney test with confidence interval of 95%. c Inverse correlation between the number of circulating VPEs and percentage methylation at CpG38 in control mice and those treated with CMV-SPR rTALE (Spearman correlation coefficient ρ = − 0.8667, r2 = 0.808, p = 0.0023)