Fig. 1
HCQ reduces and changes the localization of RNA:DNA hybrids, inhibiting the activation of interferon-stimulated genes (ISGs). A Accumulation of cytosolic RNA:DNA hybrids in the RNASEH2B-mutant LCL compared to the healthy control and RNASEH2A-mutant LCLs was evaluated by flow cytometry with 25 μM HCQ and without (NT) HCQ treatment. The data are presented as the means ± SEM, and significance was determined by paired t-test. *P < 0.05. B Immunofluorescence of the LCL derived from the healthy control and RNASEH2A- and RNASEH2B-mutant LCLs before (NT) and 24 h after HCQ treatment (25 μM). RNA:DNA hybrids stained with S9.6-specific mouse monoclonal antibody (green), lysosomes were stained with the endolysosomal marker LysoTrackerTM (red), and nuclei were stained with DAPI (blue). C Immunofluorescence of the LCLs derived from healthy controls and AGS patients with mutations in the RNASEH2B and RNASEH2A genes before (NT) and 24 h after HCQ treatment (25 μM). RNA:DNA hybrids were stained with S9.6-specific mouse monoclonal antibody (red), endosomes were stained with Rab5 (green), and nuclei were stained with DAPI (blue). D, E mRNA expression levels of IFIT1 and IFI44, two ISGs, in healthy controls and AGS patients before and after HCQ treatment. The data are presented as the means ± SEM, and significance was determined by ANOVA and Tukey’s post hoc test. *P < 0.05; **P < 0.01; ***P < 0.001
