Correction: Pre-activation of toll-like receptor 2 enhances CD8+ T-cell responses and accelerates hepatitis B virus clearance in the mouse models

Figure 2. Early application of TLR2 ligand P3C with pAAV-HBV1.2 by HI inhibits HBV replication without promoting HBV-specific immune response in the mouse model for persistent HBV replication. C57BL/6 mice received hydrodynamic injection (HI) with plasmid pAAV-HBV1.2. The mice were treated three times with 50 μg of P3C or PBS administered by subcutaneous (SC) injection at day 0, 7, and 14 (therefore designated as group D0). (A) Serological markers of HBV infection HBsAg, HBeAg, and HBV DNA were assayed at the indicated time points by ECLIA (Roche). The cut-off value of the HBsAg and HBeAg assays was set at cut-off index (COI) of 1.0. The cut-off value of the HBV DNA real-time PCR was 4.0 × 104 copies/ml. (B) Positivity for HBsAg or HBeAg was defined as ≥1. (C) HBV DNA levels in the liver were measured by quantitative realtime PCR. (D) Liver tissue sections were stained with anti-HBc antibodies (magnification, ×200). The number of HBcAg positive hepatocytes was counted. (E) The serum levels of anti-HBs and anti-HBc antibodies were detected at the indicated time points by ECLIA. The cut-off value of anti-HBs antibody assay was 10 IU/L. The cut-off value of anti-HBc antibody assay was 1.0 COI (<1.0 COI indicates a positive reaction). (F and G) Lymphocytes were isolated from the mouse liver at day 10, 21, and 77 after HI. (F) The specific CD8+ T cells against HBcAg Cor93-100 epitope were detected by Cor93-100 peptide-loaded dimer staining. (G) The functionality of HBV-specific CD8+ T cells was determined by intracellular cytokine staining after ex vivo stimulation with peptide Cor93-100 for 5 h. (H) Liver tissues were collected from the mouse liver at day 4, 10, 21, and 77 after HI. The mRNA expression levels of cytokines in the liver were determined by realtime RT-PCR. Beta-actin was used as an internal reference. Eight mice were analysed per group, and the experiments were repeated at least once. Data were analysed using an unpaired Student's t test. Statistically significant differences between the groups are indicated as *P < 0.05 and **P < 0.01.The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. The original article has been updated.