Cell culture and transfection
HepG2 cells were cultured in DMEM high-glucose medium containing 10% fetal bovine serum (HyClone, Cytiva), 2 μM L-glutamine, 50 U/mL penicillin, and 50 µg/mL streptomycin. HepG2 cells were transfected with a plasmid encoding dCas9-p300 (pcDNA-dCas9-p300 Core), along with U6-PCR product encoding sgRNA and HBV rcccDNA produced using minicircle technology. After 48 h, cell culture medium was removed, and the cells were washed twice with PBS before being cultured in fresh complete medium for the next 72 h. All results were replicated in at least 3 independent studies.