Figure 1
HCV infection reduced QPRT expression and NAD catabolism. (A) IHC staining of QPRT (dark brown) was performed and (B) the scores of QPRT positive areas were scored on liver biopsies of healthy donor (HV), chronic HCV infection (CHC) and HCV induced cirrhosis (Cirrhosis). cv, central vein, scale bars, 50 μm. (C) Expression levels of hepatic QPRT were measured by immunoblotting after C/OTg mice were mock infected or infected with HCV J339EM for 2 (#19, 108, 110) and 4 weeks (#20, 226). β-actin was used as a loading control. (D) Decay of QPRT was assessed by immunoblotting after Huh7.5.1 cells were mock or infected with HCV for indicated time. HCV NS3 and Core proteins were detected by immunoblotting for HCV replication. (E) QPRT mRNA was detected by qRT-PCR and plotted as the ratio to actin. After Huh7.5.1 cells were infected with HCV for 6 h, the increasing concentration of VX950 (F–G) or 1000 U/mL IFNα-2b (H–I) was added for 48 h. Cells were detached and (F,H) detected by immunoblotting for QPRT, NS3 and Core proteins, and (G,I) FACS measured for GFP positivity. (J) Huh7.5.1 cells were infected with HCV J399EM for indicated time, and extracellular QA was analyzed by LC-MS/MS. Full-length gels and blots are included in the Figure S5. Error bars were SEM of three independent experiments, student t test, *P < 0.05; **P < 0.01, ***P < 0.001.
