Quantification of HBV Viral Titer

The HBV titer in the culture supernatant was measured using qPCR as previously described [31 (link)]. Briefly, HBV genomic DNA was purified from the culture supernatant using the QIAamp DNA Mini Kit (Qiagen, Hilden, Germany, Cat No. 51306). For conventional PCR analysis, the purified HBV genomic DNA was amplified using 2 × Τaq PCR Master Mix 1 (BioFACT, Daejeon, Republic of Korea, Cat No. ST301-19h) and a primer pair, HBV 1399F (5′-TGGTACCTGCGCGGGACGTCCTT-3′) and HBV 1632R (5′-AGCTAGCGTTCACGGTGGTCTCC-3′). For qPCR analysis, HBV DNA was amplified with SYBR Premix Ex Taq II (Takara Bio, Kusatsu, Japan, Cat No. RR82LR), HBV 379F (5′-GTGTCTGCGGCGTTTTATCA-3′), and HBV 476R (5′-GACAAACGGGCAACATACCTT-3′) using a Rotor Gene qPCR instrument (Qiagen).